Why is her sex drive so low?

I can't speak for your girlfriend but I can say that in my experience, SOME women need sex less than you do . And they do it often when you first meet either because the initial spark of meeting someone new ignites their desire or because they're trying to please you when they first know you . Then later they let it slack off because it's not as important, in order to "keep" you, once they've got you . Of course I don't know that this is the reason . It would depend on what she said to you during your conversation . Also, if there's trouble in your relationship (are you fighting at all or does she feel jealous about anything ? ) that can dull her sexual feelings towards you . Guys seem to be able to have sex anyway but some women's sexual feelings get dulled down when things aren't going so great between you . Also, things like antidepressants or other medications can affect someone's sex drive IMMENSELY . Is she on any medication ?

I can't speak for your girlfriend but I can say that in my experience, SOME women need sex less than you do . And they do it often when you first meet either because the initial spark of meeting someone new ignites their desire or because they're trying to please you when they first know you . Then later they let it slack off because it's not as important, in order to "keep" you, once they've got you . Of course I don't know that this is the reason . It would depend on what she said to you during your conversation . Also, if there's trouble in your relationship (are you fighting at all or does she feel jealous about anything ? ) that can dull her sexual feelings towards you . Guys seem to be able to have sex anyway but some women's sexual feelings get dulled down when things aren't going so great between you .

Be prepared for heartbreak, unless you are emotionally detached from her. She is not attracted to you like she was before, hence the reason there is a lot less dirty, filthy sex going on. Run for the hills! But what do I know, I'm Just A Random Guy.

What was said during the talks? If she isn't telling you the reasons then you should examine what your needs are and whether this is the girl for you.

Remember, there are a million and one reasons that could pertain to the 'why' which range from emotional, medical, hormonal, or even the weather.

Is she currently on birth control? The pill is notorious for killing a woman's sex drive. If so, you might want to go back to condoms for a couple of months and see what happens.

The way I see it it could be many reasons.
1) The "honeymoon" is over and he takes as much pleasure just being with you without having sex than having sex.
2) He is stressed at work?
3) Something is troubling him but he either don't want to talk about it or just wants to wait to see if it solves by itself.
4) The "spark" is gone
5) You simply is in greater need of sex than he is