Wow...our stories sound similar. My AH (of 27yr) was just like you describe yours until the last year or two......he moved out and kicked it up a notch. Wanted to "have fun"....that I was holding him back,I guess. Some say it is a midlife crisis....I just call it a nightmare. He just divorced me a few months ago. Our baby just started college this fall and the older one moved 100 miles away.
Glad you found this place,it has been a huge help for me. Stick around and I think it will help you sort some things out for yourself.