talk to her.... seriously that's a health hazard to you. not saying anything will only make it worse

Sex is nice, but it's not worth to suffocate for it. Talk to her. Perhaps she will let you be on top, or maybe she can rise a bit so you actually can breathe.

Seems like a very one sided sex life. Being in a relationship means give and take in all aspects of it, including sex. Have a serious talk to her about letting you have some fun too and do something you want.

Not only is this incredibly unhealthy because of the suffocation, it also sounds pretty boring. She'll only be on top? A good sex life has variety, we all have our favourite positions, but she needs to open up more, and incorporate other things. Your sex life isn't only about her and what she wants, it's about your wants and needs too. Continuous repetition, especially in this situation, where it's becoming a health hazard, will only lead to relationship problems.

Take a deep breath and pump!

Have her turn around and rest her hands on your legs if she leans fwd. no suffocation for you, different angle, and she gets to stay on top. If she doesn't want to turn around just have her lean back instead of fwd.

I have a tall, big boobed girlfriend who has sex with me but I no communication skills. FML.

There are worse ways to die.

That, minus the suffocation, sounds awesome.

doesn't matter had sex