I left my toxic ex and have a new relationship

My ex was emotionally abusing and it was too stressful for me, I ended things. We have financial commitments so we still talk to each other here and there.

My new relationship is amazing but when I talk to my ex even for a little it gets in my head and I feel like I don't deserve my new relationship even though it's everything I've ever wanted and more. I feel damaged and I don't know how long I'll feel like it, I just feel like I don't deserve him but I know I do