Catherine "Cathy" Christine Wendy Matthews is the widow of Alan Matthews who died in 2014. Following his death, she became a compulsive hoarder. In April 2015, Cathy met Roy Cropper and eventually began dating him. In early-2016, Cathy learned that Alan had an affair with her sister, Nessa Warner. In May of that year, Cathy proposed to Roy but was turned down, soon afterwards she was run over by Carla Connor; but luckily survived the horrific incident.
Cathy and Alan had no children as a couple, but she does share a close bond with her nephew, Alex Warner, whom Alan was revealed to be the father of.
Cathy's husband Alan had worked an adjoining allotment plot to the one shared by Sharif Nazir and Roy Cropper. The two men were in their usual dispute about what they planted and this time it was over spearmint. Sharif threw his unwanted plant onto the next door but overgrown plot, annoying Cathy who had just walked up. Sharif apologised and Roy offered their services to clean up the ground as a form of apology. When she returned later, much progress had been made on the work. Cathy apologised for her previous anger, telling them that she hadn't been having a good day. Sharif was shattered after his extra effort but Roy stayed behind to continue. He later shared a cup of tea from his flask with her and she told him about Alan who had died a year before and his pride in the allotment, finding sanity in its peace and quiet from his council job as a customer complaint's officer. A day later, Cathy was not so happy when she overheard Roy and Sharif talking about taking over Cathy's plot, Roy only thinking of proposing the matter to her, and she angrily tore a strip off the two men.
She came into Roy's Rolls a few days later to talk to Roy but for some reason lost her nerve and left hurriedly. Almost a month passed by before she returned, offering to sell Roy her late husband’s elderflower cordial but the sample she brought had turned alcoholic. Upset, she left again only to return to apologise for her behaviour. Roy realised that she couldn't afford the £30 allotment fees and offered her several hours paid work to earn the sum rather than lose her dignity with a charitable offer.
Roy continued his friendship with Cathy who continued to frequent the cafe. When Fiz Stape returned to Weatherfield after an absence of six months nursing her sick mother, she met and took a liking to Cathy but both she and Tyrone Dobbs started to become suspicious of Cathy's stories about her freezer and boiler packing up and considered the woman's behaviour to be strange. After a visit from bailiffs, Roy found out that not only was Cathy in debt but she was also a compulsive hoarder, her house being packed with so many items from her life that there was literally nowhere to sit. He tried to persuade her to change her habits but became insistent after a pile of debris in her living room fell on her, trapping her beneath. Luckily Roy soon came around to her place and rescued her.
In January 2016 Cathy told her sister, Nessa Warner, that her New Year's resolution would be to de-clutter the rest of her home. Nessa - who didn't believe that she would be able to do such a thing - told her that if she managed to get a car boot-full she would cook Cathy and Roy a meal over at No.1. While sorting through late-husband Alan's paperwork, Roy discovered some old love letters from Nessa. Surprised by this discovery, Roy decided to not tell Cathy in the fear that it would break the already fragile woman. Roy confronted Nessa about the discovery, who begged Roy to help her dispose of the damning letters. As they entered Cathy's living room, they saw a tearful Cathy at Alan's desk holding the letters. Cathy decided to call time on her relationship with Roy due to the fact that he knew about the affair but didn't tell her. Cathy later disposed of the letters by setting them on fire in a bin but she briefly left the room and by the time she returned, the flames had gone out of control. Roy and Nessa called round at the house to apologise, and as they spotted the blaze, Roy went inside to rescue a trapped Cathy as Nessa telephoned for the emergency services. Following Cathy's near death experience, Nessa departed from Weatherfield.
In May, Cathy decided to propose to Roy after Anna Windass and nephew Alex convinced her to do so. The night Cathy planned to propose to Roy was also the time as Nick Tilsley and Carla Connor's wedding. Although the ceremony did take place, even after the revelation from Tracy Barlow that Carla had slept with her boyfriend Robert Preston and subsequently financially helped Robert buy Nick's Bistro, Nick had a change of heart at the reception and announced he would annul their marriage. A broken Carla asked Roy to fetch his car. In the street, Cathy stopped him in his tracks and got down on one knee and asked him to marry her. Roy, who was worried about Carla simply replied "no" and ran off the fetch his vehicle. A shell-shocked Cathy told Alex about what happened, who suggested that they bought chocolates at the Corner Shop.Just as they left the shop tragedy occurred when Carla accidentally ran Cathy over. She was flung into the air and sent flying into the wall of the Corner Shop. Cathy was rushed to Weatherfield General and admitted for observation and treatment, with Roy by her side. She was discharged from hospital a few days later, although somewhat on edge thinking Roy was going to break up with her as he hadn't spoken about what had occurred moments before the accident. As the couple went for a walk on the Red Rec, Roy accepted her proposal of marriage.
When nephew Alex expressed an interest in purchasing one of Pat Phelan and Vinny Ashford's flats, Cathy decided to take it upon herself to ask Alex's father, Nigel Warner, for the money for him to do so. However, Nigel was extremely hostile towards Cathy, and after she inquired about his despicable behaviour, he let slip that somebody ordered him to keep quiet about who had been paying for Alex's maintenance. Confused, Cathy investigated through some old documents, and later confided in her friend, Yasmeen Nazir that she believed Alex was the result of her husband, Alan's, affair with her sister, Nessa. Concerned that her theory may be correct, Cathy went to see Nigel again, however this time he confirmed that Alex was Alan's son, with Cathy taking her frustrations out on Alex. Cathy soon learned Alex knew all along that Alan was his biological father, and soon after announced that he was going to live with Nessa in Scotland, thinking that he had upset his aunt. The situation eventually took its toll on Roy and Cathy's relationship. Roy thought Cathy's treatment of Alex was wrong. He soon came to the conclusion that the couple need some time apart. On their way to Scotland, Alex admitted that he didn't want to live with Nessa and he moved back to Weatherfield. Cathy and Alex called a truce and she reunited with Roy, resuming their relationship.
As their wedding loomed closer, Cathy's excitement was obvious whereas Roy felt nervous and was unsure if he had made the right choice to go through with it, as he still loved Hayley deep down. In December, Cathy's troublesome sister, Nessa, returned for the wedding and desperately wanted to be involved. Upon Nessa's return the stress really started to tell on Roy with him developing rashes on his face, sleepwalking, and he even suffered a panic attack in the Bistro. Despite all of this, Roy agreed to go ahead with the wedding just to keep Cathy happy.
To make sure said her vows correctly, Cathy recorded her words with one of her several dictaphones. Upon reciting her lines, she left the dictaphone switched on as she left the flat for her hen night celebrations with Yasmeen and Nessa. While out, Tyrone and Brian Packham confronted Roy about his feelings towards the wedding. Roy admitted to them that he was only marrying Cathy because he promised her when she proposed to him, however the trio were unaware that Cathy's dictaphone had just recorded their entire conversation. On the day of the wedding, Cathy was joyful as she prepared to marry Roy. She was confused when she heard that Tyrone and Brian had been banned from attending by Roy. Upon arriving at the church, she finally allowed Nessa to give her away. Outside, Cathy listened to her vows one last time, but instead she hears, by accident, Roy confessing his true feelings about her. She entered the church with a calm facade and confronted Roy and the guests, asking everyone except Roy to leave the ceremony. After suggesting that they remained close friends, Cathy was crushed by Roy's enthusiasm at the prospect of them splitting up. As a result, Cathy and Alex moved out of Roy's flat and Cathy moved in with Yasmeen at 6 Coronation Street. Before Nessa went back to Inverness, the sisters got drunk together and reminisced.
Following Roy and Cathy's split, Cathy left her job at Roy's Rolls and picked up a job at Prima Doner and the Corner Shop in 2017. Both businesses were owned by Dev Alahan. Dev gave her both jobs after unfair treatment when Gemma Winter employed her without permission. Cathy and Gemma developed a friendship and decided to hit the town one night. Upon arriving back, a drunken Cathy vomited on Brian's shoes, but later apologised to him.
- Cathy's sister Nessa has a son named Alex, who came to visit his aunt in September 2015.
- Cathy is a talented artist and occasionally teaches art classes at Jamila House Community Centre.