Were you having sex before that? If you were, this is a big problem. If you weren't, is she just waiting for marriage? Anyway, to address your question... If in a relationship, I can't go very long without sex. Sex is one of the main parts of being in a relationship. If you stop having sex, then that just makes you friends or something. The point is to be intimate with each other and what's more intimate than having sex? If not in a relationship, sure I can go without having sex for a long time, but that doesn't mean I necessarily want to. The need for it is different though. When in a relationship, sex is about being with your partner and also for pleasure. I can't understand how you can be in a relationship without sex, unless you're waiting for marriage.