Oh my.. I truly feel for you!! I'm in similar shoes as you and am unsure as to what to do as well!! I'm 33 and the man I'm suposed to spend the "rest of my life with" was with another woman (one he KNEW I didn't like) while I was prego with our son!! And now.. here I am 7 years later with a beautiful son (who will be 7 tomorrow

, still living in a separate house from my "beloved", with no engagment ring, but even just today was made many more promises of a better tomorrow... blah blah blah...
I, like you, have been dreaming a nice family life, but also like you, he hasn't stopped talking to his past partners... as a matter of fact I caught him in March 2010 with txt messages planing to meet up with a woman he dated in HIGH SCHOOL!! He's 39 years old!! Wow.. I'm triggerin myself here...
Anyhow.. I feel you pain and confusion and know how hard it is to let go of the past.. but like I say to "mine" how can I let go of his past when he won't ? I see no reason for these men to be even saying hi to these women in passing!! JMO