I quit depo about a year ago, after being on it for 5(!). I'm in a long term relationship with the man I plan on marrying, and he was very supportive when I went off depo. I gave up hormonal bc altogether and started using a diaphragm/condoms instead, and am SO HAPPY with my decision. I never had any major side effects with depo but always worried about what all those drugs were doing to my body.
I experienced pretty big mood swings for a few months after quitting, and I had a ruptured ovarian cyst which the doc said could have been caused by my body "trying to adjust".... that was a little scary, but hasn't caused any further problems. I started getting periods about 3 months after it was out of my system (so, 6 months after my last shot) - the first few were heavy, but they have been normal ever since. In fact, they are much more regular now then they were before depo.
I didn't lose or gain any weight, but I didn't lose/gain any weight while on the shot either.
Good luck getting fertile ;)