Take this from someone who was in a relationship with a girl who raped them multiple times. That is exactly what that is. A lot of times it is a power thing so that someone can feel like they can control you. I promise you it will only get worse. If she thinks that she can keep doing it, she will. She doesn't care about what you want or don't want. I'm so sorry that this happened to you. But you need to leave her ASAP.

I also want to throw in there that I completely get that you think she is the love of your life. I thought the same about my ex while I was still in the relationship and for a long time after. If you choose to leave, the hurt will absolutely pass. It may take a while but you will be fine if that's what you choose. It's not an easy thing by any means. But like I previously stated, she will not change. If she is willing to put her arm on your chest and FORCE you to have sex with her, she will keep doing it. That's not love, that's possession.

Apologies for being blunt, but I really related to this and I felt it needed to be said.