It's just not good anymore

I've been with my boyfriend for almost 2 1/2 years. When we first started having sex it always seemed to be great. As time has gone by it has gotten worse. It had gone from being really good sometimes, to good sometimes, to rarely good at all. I don't know if it is me or him that has the problem. It just doesn't seem to feel good for me anymore. I don't know what to do. I just want my old sex life back.
Any comments or suggestions would be greatly appreciated.
Thanks!

I'm not an expert on anything, I'm only 18, so what do I know, right? Although, I know enough about relationships (and yes, sex is a big part of a relationship) to know that communication is VITAL!!! Tell him how you feel, and what's wrong.. During sex, if the flow isn't going, try telling him what to do and what not to do. Remember.. communication is SO freakin important in all aspects of a relationship.

I'm basing my answer here on the assumption that he doesn't know anything about the sex being bad. If he knows, then I have no clue at all as to what to do.

By the way... this is my first post so uh... How's everyone doin?

Is the sex its self bad, or is the problem a lack of sensetivity?

I was wondering that, as well.
Is the relationship fine & dandy in other areas? Could you both be going through the motions (i.e. sex), when truly, your hearts and emotions are not into it.
Even in a strained relationship, sex is one of the things that re-connects two people, if only for a short time. If THAT isn't happening, could be time to re-evaluate your personal goals - things may not be as permanent as you thought.
I agree with Fromonkey - try to talk about it. After 2 1/2 years, its certainly worth going the extra mile to work things out. Just be prepared - sometimes this could indicate the beginning of the end. I really wish you luck, and welcome to you AND Fromonkey!

When I was a teenager, we didn't have MTV.
We had to take drugs and go to Rock Concerts!

I think Infornography is right. It is the sensitivity that's missing. At least I hope it is that, and not as serious as Rose mentioned. We've tried different positions, and have talked about it a little bit. He's getting frustrated though, I think. Because it isn't feeling good for me he thinks of it more as me doing him a favor, and doesn't like that. I previously tried searching the internet for anything that could help to make sex better. Which is where I stumbled across this web site.
Thanks for the imput though