it sounds like the reality of your NOW is really catching up with you.....seeing just how far in the past the "good" time were, how much he has changed, how much YOU have changed, and it ain't all rainbows and unicorns.
sweets, we ALL wish to return to younger carefree days....i'm 56, and i'd pay good money for another day at 47, or maybe just to have the knees of my 38 year old again. days before being a home owner, a dog owner, a mom.....back to the days when i took that first temp job, before i knew that i would be at the SAME organization 25 years later.....or any day PRIOR to hot flashes (that's a 16 year and counting run).
you're going thru normal natural grief and contemplation.....while working on accepting the new NOW even when you don't quite know what that IS yet........