<human>: To start with, this is the first time I've been in any long-term or physical relationship, so I don't really have a frame of reference.

My boyfriend and I were great friends before we started dating, and we have really good chemistry, but we have very different takes on sex. Every time he and I are in bed together, he wants more than just cuddling and sleeping. It irritates me because I feel pressured and like I'm letting him down if I don't want to do anything more physical.

On the other hand, the way I deal with sex is, in general, to see it as just another need that requires fulfilling: more about the destination than the journey, as my boyfriend puts it. It's not that I don't get turned on or feel sexual attraction; it's just that I feel it's not worth going through this long and tiring process (like my boyfriend would prefer) in order to satisfy that desire.

I'm feeling overwhelmed by it all; should I give in and have sex with him all the time, even though I'm more exasperated than enthusiastic? As his girlfriend, am I being selfish by not doing so?

Summarize the given text in a few sentences.
<bot>: My boyfriend wants sex all the time; I want sex only rarely, and even then I don't care about it all that much. What should I do?