AITA for calling my gay friend fake?

So I 24f was invited last week as a plus one by my friend J(24f) we went to a birthday luncheon for one of her friends, almost all the people that were attending are gay(about 3) I was the only straight one,anyways all was well and I was having fun until the topic of discrimination and gay rights and stuff came up,I honestly am clueless on it and I kept quiet coz I didn't wanna offended anyone and I guess after a while they noticed and asked I said it's because I don't know what's it's like and I don't want to pretend I do. J chimed in and told them I was a "straight Christian" so I it was best I kept quiet,that opened up a can of worms. The whole group turned on me talking about how my community is terrible and all that and am terrible person for not standing up for J when she was shunned. Now J and I grew up in the same christian community and when she came out at 19,her parents didn't accept it and she left. What I know I know either from her mouth or the grape vine back home. I usually keep my nose out of people's business unless it includes me in someway. I honestly think J is an awesome,she's bubbly,has a big her and her being gay never changed that. Back to the party,a was bombarded with questions like "Why are you hanging out with sinners like us" or "won't you preach to us that we're going to hell" and things of that manner,it was honestly alot and I couldn't get a word in coz I suck at confrontation. I told them I care for J like a sister and her being gay never changed that for me They said then am not a true friend because I would help her "Come out of the sinful life" so that she doesn't "burn" The conversation went in for a while and when J started throwing in comments about me being bigoted (I don't know what that means" I figured I over stayed my welcome,so I left. Later that night J started calling and texting but I honestly didn't have the energy because what happened was quite confusing. I avoided her calls since then and this morning one of the girls called me saying I was an ahole for ghosting her when I was one of the few people that she had and whatnot. More confusion coz she gave off different picture at the lunch. I told my mom about what happened and she said that while she understands my feeling I should still be there for J because it's not easy being different and she needs all the support and now I feel guilty. Am still so confused about what happened or maybe am just stupid. Am sorry if this is all over the place. Plz help.