So I have an issue. I don’t even know how to start.

I’ve been with my boyfriend for 1.5 years, he’s 29 and I’m 26. After seven or so months, we broke up for a few weeks because he wasn’t sure about his feelings anymore. After three weeks or so, we met up and he told me he knew that he loved me, had never been so happy with anyone before, that I made him feel so good. (This is a repetitive thing he says „you’re so good for me“.)
Well anyways, it was horrible for me, but I forgave him, understood he got spooked (or something) because he was scared of the seriousness of the relationship.
Fast forward to now, this Monday we came home from a vacation and had a wonderful time, a lot of intimacy etc. and him being affectionate etc. (Which he is always). Now today, he said he didn’t feel very attracted to me and I told him that this was normal, since we’ve been living together (!!!) since August and have just spend 24/7 together for more than two weeks.
Now it has spiraled out of control again to where he said he wasn’t always sure I was „the one“, that he loves how good I am for him, how perfect our relationship is. But again, he is questioning his feelings.

I guess my very straightforward question is: Should I just leave? Does he have huge issues with intimacy or does he just not love me? (He’s only had really toxic, abusive relationships so far)
I’m oddly very calm about this situation since it’s happened before and in the back of my mind I have feared exactly this from happening again. And I will put myself first, take care of me, and look inside of my heart to find out what I want now.

My take on love is: you either do or you don’t. But is it that simple?

Please tell me your thoughts.