He’s a green flag- but I’m unsure

We’ve been together for a couple of years. As the years have passed, I feel like we shifted apart in terms of ambitions, interests and environment. I grew and he didn’t. He is, however, an amazing partner - caring, loving, supportive, forgiving and always working towards solving all the problems we have. He has a calm, cheerful personality. He would be an amazing father for the kids I want to have one day. He’s basically everything I could wish for… but it doesn’t feel like my heart follows. I feel limited physical and intellectual attraction and connection, more of an attachment than chemistry or “my fav person” feeling. I am doubting myself a lot, especially since my family has some dysfunctional history and myself I also have a history of choosing the wrong people (abusive, emotionally unavailable). I even started going to a therapist to untangle that but she keeps pointing out that it is about my need for connection not being met. I cannot agree with it somehow I feel like I might only be able to connect to people who are not fully avaliable and keep me on the edge. Or maybe not. I really don’t know. And I keep asking myself- should I stay and choose the future I want with a risk of feeling emotionally unfulfilled or should I leave, risk never starting a family on time or even not meeting a better person and ending up with regret (or in a good scenario - meeting the perfect match that I was always hoping for).