Some of the things I can relate to:
Definitely identify with gaining weight. It's brutal how quickly you can fall out of shape.
After playing basketball 6 times a week since college I barely get out once every three months. I'm 30 now and feel 40.
Aside from the up and down roller coaster ride, the hardest part for me has been balancing a relationship that began at roughly the same time that my co-founder and I went into business together. I have no idea how you could possibly balance anything else (like a real job) outside of a startup and a new relationship for extended period of time.
There are times my relationship has been a distraction to our business. But well worth the juggling act :)