i just recently started dating this guy, and everything goes great, until we get to sex. he gets really nervous and worried about everything. foreplay is good but he falls short when anything starts to happen. he says that when he does the things by himself he is fine, but when i am around it hurts and makes him uncomfortable. i have told him that he needs to relax more, but he tells me that he doesnt know how. how would one go about practicing to relax?