oooookkkaayyy. Some weird ass answers going on in here.

First off, don't do the petty revenge thing "if she's not going to have sex with me I'll just be a jerk and then she'll come around." That'll do a lot more harm than good most of the time if you're actually interested in staying in this relationship. And the post above this one... that's just stupid. Human bodies don't work that way. Weather does not affect people's emotions. We may relate certain emotions to some weather, but its sure as hell not causal.

OP, you likely just need to be assertive. Don't just "ask" for sex as you said you're doing. Get into it. Do something nice for her, relieve her stress and get her in the mood. I'd think if she was stressed out some sex could do her some good. Then again, some women just don't have strong sex drives or won't until their late 20's or 30's. Just the way it is. If you can't handle that fact or change it, then its up to you to make a decision about staying in the relationship.

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I'm drowning in assholes.