As Robert Heinlen said in one of his books, Masturbation is Safe, Healthy, Moral, Socially responsible, Doesn't make you go blind
- But it sure is LONELY !

Everybody should have a few casual relationships - it's a learning experience. The main thing is to try to be FRIENDS as well as sexual partners and to be honest with each other about the way that each of you views the whole thing. At least you get some idea about what you'd want in a more permanent relationship if you ever intend to have one.