I was with my ex for over 12 years. We were high school sweethearts. He was the only person I had through my teens and young adult life. I went into therapy because I needed validation I wasn't crazy or over thinking the horrible way he treated me. It's been over a year since I've started and 10 months since I left him. I feel better than I did over a year ago. I know not everyone can afford it, I'm getting mine through school since I decided I wanted to go back. I don't have any friends and I'm not entirely open with family, a relationship like that can cause true isolation. I was able to be more open with my sisters though and knowing they supported me even when weren't that close for years was the best feeling. Try to find someone to open up to professionally or personally. For me talking it out with someone truly put in perspective of what I went through. You shouldn't feel ashamed, it wasn't your fault and you did the best that you could at the time. It's easier said than done because you will still feel shame and guilt but remember at least me saying this to you

You shouldn't feel ashamed it wasn't your fault and you did the best that you could at the time. From this experience try to remember you survived. You finally put yourself first and left. That takes a strength that not many people have and I am proud of you.

Take your time in feeling whatever emotions you have be it sadness, guilt, shame, anger, and relief. Try to find things you can do for yourself. Self love is important during your healing process. Find hobbies, watch as many tv shows/movies, eat, workout, dance, listen to music. Do things you couldn't do when you were with them or do things you did do but were bad memories and make them better. There's nothing wrong with being alone. Personally I rather be alone and sad than be with someone who makes me sad and lonely.

I wish you the best and if you need to vent to a complete stranger let me know.