I'm sorry to hear that. And yea, it sounds like your head was not in the right place. And it sounds like you were really hard on yourself. You can't change the past, unless you invent a time machine. So all you can do is be the best version of yourself in the present and the future. I myself have a lot of regrets as well and things I could have done better in the past, but as I said, I don't have a time machine. All I can do is learn from it, and try to do things better now. I'm sure you'll go back to enjoy running once your head is in a better place again. Reaching out to a therapist was the best thing you could do.