Should I ask this guy out.....he's my BFF's ex?

well its not bad that you like him but it does create problems. I think 2 weeks is too soon to do something, give it a bit more time. I would sit down and talk to my friend about it, tell her how much you love him, how you feel etc., if shes over him and completely understanding she wont mind and will tell you to go for it. But that usually doesnt happen so be prepared for a small fall out. Honestly its kind of a rule not to go out with a friends ex but if you feel that strongly then i say go for it. But i was in this situation before. Be prepared for her to say no to you going out with him she may even get mad. And also be prepared for him not wanting to go out with you since your his exs best friend. The worst thing you can do is go behind her back and ask him especially if it doesnt work out with him so dont keep it a secret. Good luck :) x