[shuriken]

Well It really all depends how bad the break was. It seems that even though it hurt, it wasn't really that messy. If you're able to e her friend without harboring any bad feelings or bringing up past memories constantly then by all means. I wasn't able to do that 4 times out of 5.
Out of 5 girlfriends that I've had I'm only on speaking terms with 1 because one of them hates me, another moved away and we just lost track of each other and the other two it was so messy I had to get away from them to avoid doing something stupid. Everyone and every relationship is different.
My advice to you is keep your head up. Rewire yourself to being single for a while and don't jump into anything. Cry, vent and talk about it only as much as you need to. Breaking up with someone you care about really sucks and its like relearning who you are without this person.
Also how old are you dude? I find the older I get, the easier it is dealing with break ups. Then again the first cut is the deepest right.
Anyway hope this helps. Got out of a messy relationship myself this past July and while I'm ok, it took a while to readjust myself.