Getting hurt like that doesn't matter if your 16 or 60. Betrayal hurts and it sucks.
I always used to hate hearing that "Life goes on, there are plenty of other fish in the sea" Because when you're heart is breaking the sea seems like an awfully lonely place.
It's going to suck for a while, there is little to nothing you can do to change that. I always found that throwing myself into my work or hobbies seemed to help a little. At least it's something to do that isn't sitting around thinking about your ex. Spend some time with your herps, give everyone's cage a good sterilizing. That should kill at least an afternoon or so
Post here when you feel like it. For the most part this seems to be a pretty understanding crowd.
Hope things move on quickly for you, we've all been there.