Don't know if this will help, but I'm like that myself.
I do not like people touching me. I must give off a VERY strong vibe, too, because I see people on occasion who are touchy-feely by nature literally recoil mid- touch when they attempt to touch me. Mind, I say nothing to discourage it-my body language says it all, even when I DON'T WANT IT TO...
I rarely was OK with PDA, and I think the men I dated /married were not too bothered by it, however, they were bothered A LOT by their having to initiate any kind of sexual encounter ALL THE TIME. Both my first and second husband would REALLY get pissed about it...
I loved the men I was with dearly, I did. I just was raised in a home where we were in essence literally ignored unless we did something wrong. We were not even SPOKEN to.
So, your BF....he may very well love you dearly, he may just have a very hard time showing it. To this day (I'm 48) I have a very hard time with any type of physical affection.
Oh...DK if being RC would have something to do with it, but if he's a conservative practicing RC, yeah, that would hinder PDA, too. You just don't DO stuff like that.
( I was raised in a Catholic home for about 10 years)
However, if you are having sex, nope, he's not really serious about the RC thing.
I wish I had suggestions to help you and the BF. I really don't. I just feel for both of you. I can relate to the BF, it's really painful to feel trapped like that....having a fear of expressing yourself...
I'm guessing the BF and wife have a poly relationship? or she's separated from him?