How can this be applied to the OP's request for wisdom, the good and the bad, help in understanding relationships...

I'm of the mind to comment that when relationships go bad (and I've been there, as close to divorce as you can get and not actually be there) it's never just one person's fault. It's always easy to point a finger and blame, but it's rarely the actions of just one person that makes a relationship go bad. The choices that build up to bad situations may not always be obvious, and we may not even be aware of them as they may be part of our internal baggage that we all have.

The best thing that ever happened to DH and me was a very good marriage counselor, a no nonsense type who got us both to pull our heads out of our asses and quit finger pointing, and to look at ourselves: both of us. It was really really tough as it is so much easier to blame everything that goes wrong on the other person.

I feel blessed to this day that underneath it all we both wanted to fix it, and were willing to do whatever it took - I know that is not always the case, and that some things aren't fixable. It was very very tough. I think plenty of folks would have bailed and not stuck it out, and maybe even repeated the same mistakes that got them into the place they were at becuase they didn't get at the root of it. And Ladies, I'm talking some messy, ugly stuff. I'll spare you the details. But we did it, we stuck it out and rebuilt, and I have a marriage I only could have dreamed of 10 years ago.

i.