When you need to heal from relationship trauma, where do you start?

I have been going through struggles in a very dear relationship of mine for a year now. Within the past few months, my partner has been working on herself and her self-love and growth. This is excellent and I am proud of her for her self healing. This doesn’t come without jealousy and fear though. Within the past month, she has met someone else, is interested in seeing where it goes, but says she still loves me more than she has loved anyone and that it’s different.

I am struggling to understand where to go from here. She has told me and I know that I need to focus on my own healing and leg care, but I’m not sure where to start. I’m not sure how to stop the thoughts and images that spiral through my head about her new relationship. I’m not sure how to cope with the loss of her.