I have shared this before, but in reality most men will never truly get it. This will be a loss for both, but it requires a lot of talk and conversation in "handling" the needs and concerns of both.
I say I get it, because I "know" the damage from being raped. I know the tying of pleasure to pain, that our bodies have associated in our minds to deal with the extreme violation.
I know how to watch and observe how to take that submissive alpha woman (or truly submissive), and use the appropriate shock and awe, and conversely, because I "know" how I have to had to turn off my emotions how to drive down deep to give her the ultimate fantasy.
I also know while she is screaming AND creaming "No No No" as I throw her with my huge body and physical presence, I grab her head and pull the hair back and bend her over "her couch" in "her home" (really ours) and rip her skirt or pants/panties down and take her hard (I will have put lube on my cock or have a lubricated condom), and I thrust with my several hundred pounds of weight and muscles that the couch moves .. and she grunts.
If she issues a safe word ... I pull out, I stop I pick her up and hold her and hug her and say "I am here X, it is me Alan, I love you and I am sorry it was too much". Your are in control. As a natural switch, if she is needs to let it out physically with pain, I would grab her hand and say ... my safe word is X ... release the pain.
Guys that have not been raped and powerless, don't get this. The reality is I don't want this knowledge, I fucking hate it as it destroyed parts of me forever, but with a partner where trust is there and established, we both can fight and heal the anxiety demons and fear trolls and take back the power since we all know the submissive is the one in charge.
So talk talk talk, make sure boundaries are set and communication always happen, and in the above example ... one doesn't go from vanilla sex to that after one "session", this is the build up that happens after months of talking and playing and working towards.
I know writing about this was hard, so hugs to you and I hope you heal and live and love fully!