I can understand what you're saying ~ how you're feeling.

There are good signs though: she's open enough to share these ideas with you, rather than holding them inside. You could try tying her hands together, above her head, & covering her eyes with a bandana or eye shades to slowly and gently surprise and dominate her. That doesn't take a lot of strength, just willingness from you and her.

It also sounds like part of the problem stems from personal insecurities that you hold against yourself. Working on those separately would help you be a lot happier and more confident. Maybe that entails seeing a T (therapist) to help you; or taking a fitness class (like pilates) to strengthen yourself and become more limber, relieve stress; get into some enjoyable activity outside of the relationship (for you). Like art, dance, hiking, photography, writing, music, etc.. Something enjoyable that you can say, "Yeah, I did that. It feels good to me!"

Lastly, to Psych Central. I hope that it's a positive and helpful experience to you.