This is interesting, because I think this happens A LOT.
You get to that threshold, the "make or break it point "and either you bail out because you are scared of the hurt, or he does.
What's funny is that when we are young we love in a truly unconditional way. Apprearances mean almost nothing, look back at some of your ex's and you probably say "WHAT was I thinking?!!!" But early in life we love with ALL of ourselves, because we've never experienced the hurt.
Once we have been hurt, we shield our hearts or we panic when the final moment comes.

Most fascinating of all, to me, are the ones who BELIEVE in their hearts that they aren't good enough for you. They are afraid that your heart is too pure, you job is too good, you faith is too complete. They are afraid of messing up and feeling the pain of their actions, so they walk away and choose to be with another who is equally 'flawed'  in their opinion, because then there is no standard to live up to. When a man tells you that he's not good enough for you, TRUST HIM. Wish him well and watch him walk and KNOW that he is clearing the path for your yet to come!

But, Sis, at some point, we have to suck up the fear, trust God to give us exactly what is for us and KNOW that nothing can take away what God sends TO YOU.

When the moment comes step out on faith and just see where it leads.  It may not always lead where you hoped, but it is always to exactly where you are supposed to be.