asslamau alaykum
I guess it's hard because usually the girl is more likely to be stringed along. It all depends on the situation. Always do what you think is best, long with istikhara. Remind yourself why you're doing it and don't let anyone make u doubt ur decisions unless their suspicions with various things prove true. The biggest mistake I've ever done (repeatedly, too) is follow other people's advice when i didn't agree with it, I end up resenting myself for followng their advice and then for being wrong.
You know ur situation best, and at least if you end up being wrong - you only have urself to blame. It's a reassurance for me, anyway x
edit:
God I'm pmting again
I've cried twice today. I'm off to get some pepsi though it's raining.