Loss of relationship due to accident

I was dating my ex for a year until I accidentally gave her 19-year-old cat's medication earlier than scheduled, which resulted in her having medical complications and having to be euthanized. The relationship ended quickly from there because I had to leave the house. I would never hurt her or any of her animals; I cared deeply. Instead, she tells everyone that I'm a murderer and that what I did is unforgivable. It hurts so much to see her in pain. I stay away because I know she doesn't want anything to do with me. This week was tough because the cat's passing happened around this time last year. I'm in therapy and working on focusing on myself. I've managed to regain my independence since I was kicked out of the place we lived. She also said I was with her just to have a place to stay. I never asked for money, and I always paid for whatever was needed in the house. Even without a steady income, I found ways to survive while she was financially secure, supported by her mom and disability. I know the relationship wasn't balanced, but I still care and feel bad about everything that happened. She knows how genuine I am and that I cared for her as no one else did. She was the happiest ever. I haven't reached out because she doesn't want any contact. It hurts...