this is quick, I haven't gotten to check out your post on infidelity, but there are several others on the board dealing with walkaways in crisis in their late 20s-early 30s. Some people think of it as an early MLC, or a quarter life crisis, though they are different. Astrologically (if you're into that) people call it Saturn Returns.
People to read up on would be One Day, Beth83, and Essie (in Midlife). I am sure there are more, those are just the ones that I know and post to! And me too my BF left me when he was 29 1/2
When I first got "hit by the bombs", I thought it might be MLC, but the more I learned the more I realized it wasn't MLC, it was a bunch of differnet stuff. in the beginning I WANTED it to be MLC because I felt like then I could fit his behavior to a pattern and "know what to do." But now I am relieved that it wasn't MLC because MLC can take soooo long to run its course! In the beginning I just wanted someone to tell me what to do, and didn't realize the importance of doing my own detective work on my situation--what works, what doesn't, experimenting, monitoring results, etcetera!
also, I would try moving from infidelity to "newcomers" because you will probably get more responses in newcomers!!