Hey mitz, I remember you from way back....
I think the same as what Phoenix said. What do you want, and also, what do you hope or expect to have, in the future?
If this man has never married by this point, hasn't been unhappy with his life, and has repeatedly chosen to end one relationship after another when they no longer worked for him, what are the odds he'd want to change his legal status, no matter how good he feels about you? It would be a huge change in his lifestyle. One thing you know this man doesn't carry around is a supply of happy marriage memories, like a widower or a FBH might. His style has been to go through life much more unattached.
Your desire for a "real relationship" suggests that the right man for you should be a man who lets you know without being asked that he's met the right woman (you) and would truly prefer to be married (again) to you, and who will freely express those things without being prompted.
I confess the big mistake I made when I was dating a never-married guy (my SAWH) for 4 stress-free years, was to assume since we were enjoying each others' company - the weekends spent together, the nightly phone calls he made, the approval of friends who assumed we were "a cute couple" - that it was fine for us to live in the 'here and now.' At first, I wasn't in any big hurry, either. But I eventually noticed he never, ever talked about dreams for his future. I thought he was just so content to hang out with me when he wasn't working 60 hour weeks that he had no need to talk "future!" After 4 years, though, I felt like we were in a stuck place, not moving closer or leaving and I knew I'd have to break up with him if I wanted to find a long-term partner.
Long story short, we did get married, he didn't want to end it, but afterwards, it was clear I'd wanted a "permanent relationship" way more than he did: I found out years after we married that he had been hiring prostitutes "every so often" throughout our dating years! I never suspected...except once when he failed to call late at night on a road trip and I thought "out with the boys, doing who knows what." Meanwhile, I turned down any other opportunities to meet new people, out of loyalty and contentment with my steady part-time BF.
Not saying your old high school friend is like that, at all! Just trying to share how when I'd felt "something maybe is missing" during our relationship, it was my gut trying to tell me my BF actually wasn't "all in." And I didn't realize....
Your gut is also picking up clues, like his saying he wants to "take it slow" and not "meet your folks." Translated, I think that means he's on the fence, wouldn't you agree?