Is it possible that he's truly not gay? Or is he in so much denial/so tormented by religion?

I'm 25, met my boyfriend/friend/ex two years ago. I've been active on /r/askgaybros posting about all my relationship drama, but I decided to post this here because I'm looking for a more mature discussion regarding this.Obviously none of us know exactly why we are gay, but I think we can agree it's a combination of nature/nurture. My friend believes that homosexuality is caused by weak father relationship, manifestation of loneliness, or molestation (this is what the Catholic church states).I can prove this to be false because of my personal experience. I have a great relationship with my parents. I majority of my friends are (straight) guys. And I never was molested.My friend's personal experience is this: When he was 15 he had a friend of the same age, and they messed around a lot sexually. Then he hooked up when he was 16 with a guy who was 26. Even though this was consensual, it's obviously borderline sexual abuse.This led to him doing a lot of hooking up between 16-18, then he got really into religion from 18-20. Then he started hooking up a lot again, and going to gay bars, etc.Then he met me right before he turned 22. On Grindr. We hit it off really well. Became super close friends, lots of cuddles, we didn't even start having sex until like 6 months into our relationship.And during this time, he told me several times (and continue to to this day) that he is not gay, and cannot identify as such because it's in conflict with his faith. In addition, we cannot be in a relationship because it's in conflict with his faith.He says all of this is just a result of him being exposed to sex at a young age. And that believing he's gay has done "harmful things" to him, such as leading to hooking up and living the stereotypical lifestyle. He describes his past experiences as traumatic, and it's like PTSD. He says cuddling/being intimate with me brings back those bad unwanted memories.He fails to realize his sexuality isn't the cause of this, but it's the way in which he chooses to express his sexuality. To him there is no "normal" because according to his beliefs romantic same sex love cannot exist. So it's either a) be celibate or b) superficial encounters.He also tells me that he's not going to "sacrifice his dignity" by being in a relationship me like it's some terrible humiliating thing.And of course all of his Catholic influences (friends, priest) reinforce these ideologies and constantly "keep him in line" and tell him that he isn't gay, needs to go to confession, etc. They also give him hope that he can marry a woman someday.Despite all this, it's obvious he's attracted to me because he initiates affection, flirting, etc. all the time. He's been my boyfriend in every sense of the word.I found out he was Catholic when we first started dating, but I didn't realize the extent of the internal conflict he was dealing with. I found out he cheated on me last June, and he just lost it. He visited this priest he used to go to for spiritual guidance who told him to distance himself from me and end the physical portion of our relationship.From June through December it was just a mess. Then in December he came back into my life and things were relatively ok. The priest came back from an extended trip in January, and he's been visiting him on a weekly basis. Two weeks ago, he told me he needs to refocus on his spiritual life and things have been a mess since. Yesterday he apologized for "seducing me".