Different strokes for different folks.

I think your girlfriend would probably have found a way to say something by now if she was concerned. I mean she's still with you isn't she? She can't exactly find you repulsive.

You don't say whether it's you who's withholding more intimate moments with her or whether you've noticed a change in her attitudes towards you. You also don't mention your age range - if you're both still virgins or you're each others first serious partners then these things can take a while to come about and feel comfortable with - don't rush things.

If you're out of shape there are things you can do you've just got to keep level headed about it. Improving muscle tone and general fitness levels are also likely to improve your self esteem.

Just to reassure you, as a woman i don't like overly muscly men. I much prefer them in a more natural state. For me, if someone likes themselves and strives for good health...s'all good