I've been on the pill for almost a year. now my boyfriend is in a different city and we may meet only once in 2-3 months. should i stay on the pill?

Yes: The pill will not work if taken sporadically. It takes time for it to change the hormonal patterns. You must take it as written.

Infrequent sex: Yes. You should remain on the pill unless you are 1) trying to become pregnant, or two going to switch to another form of birth control. If you go off the pill and do not use another form of birth control, you could get pregnant.