But that's just a lot of water
take your time. there's no rush. are you making forward progress in your ability to trust? doubting him a little less over time? watching his actions? you haven't been in a relationship with him that long.
I'm 3.5 years in to my relationship and I still have an occasional moment of worry. They are much fewer and farther in between now. Many many months apart but it happens.
Don't focus on being all the way over that part of your XWW. Focus on healing and getting better. Counseling helped me tons. I'm very good at identifying an unfounded worry v. SOs actions not matching his words.
Example: SO went out to lunch the other day. He was off and I had work to do. I checked his bank account to see how much I could transfer for bills and there was a charge at a restaurant that was clearly too large for 1 person. HUGE trigger b/c this was one of the ways I found evidence about my X. He came home. I waited and didn't confront b/c nothing else was sending up red flags. He had lunch with his BFF. He happened to have something with him that BFF had previously borrowed so I'm sure he saw his friend. I controlled the feeling and waited. I was reassured. Awkward confrontation avoided, further deepening of my trust validated.
Underneath a bridge I burned
And there's no use in backtracking
Around corners I have turned
“Many of us crucify ourselves between two thieves - regret for the past and fear of the future.” -foulton oursler