Should not have told mom I have OCD

Being raised by my mother is absolutely a tremendous factor in the mental health issues I have today. I knew in my heart I should not tell her I have been diagnosed with OCD, but on this last trip to visit, I felt vulnerable enough and went for it. She at first seemed like she would respond appropriately, said "I'm proud of you" when I said I start ERP after the trip. But then that made me let my guard down and share some more, and that's where it all went wrong. I say that I have moral OCD, and I am very worried all the time about being good, and after every interaction I will replay the conversation looking for where I might have said something bad without meaning to. She says that she has something similar going on. You see, my dad's brother's wife doesn't send her birthday cards. And my cousin (the daughter of said brother and wife) posted a comment on instagram on a post somewhere saying something bad about sister in laws, which obviously must have been about my mother. And look at this card my mother got from her students, doesn't this prove that people like her? And all she has in her heart is kindness and goodness, and if people don't see that, that's on them. And that was the end of the conversation. So...... making it about herself was really helpful, I guess. I didn't know not getting a birthday card was just like having OCD, but I guess you learn new things every day. Needless to say, I was devastated after this and felt like a supreme idiot for telling her when I knew it would only end in tears. Not sure what else to say, just wanted to tell someone.