Definition: Given a real-life anecdote of a complex ethical situation, generate a suitable title that describes the main event/root cause of the situation. Imagine that the given text is a social media post, and you have to write the title of the post, so the users can decide to read the main text or not.
Input: My fiancee is no longer really speaking to her mother for unrelated reasons, but her mother recently texted her saying I was a "psycho bitch" for this particular incident. I'm wondering if maybe I was in the wrong.

My fiancee and I are a same sex couple and have been together going on three years. We've lived together around two years, including around a year in our current apartment. Her mother came to visit a few months ago, and I wasn't totally thrilled (she is very religious, conservative, and anti-science. I usually just avoid those topics, but it bugs me hearing about how she treated my fiancee when she came out). Anyway, she kept trying to bring up religion (I'm agnostic, probably leaning toward to atheist side of things) and I was polite, but would change the subject. For example: 

FMIL: Where do you go to church?
Me: Oh, my sister used to sing for the church choir at (redacted) Episcopal, so I still go there when she's visiting sometimes.
FMIL: Well, [fiancee] can't get married there with you. We're Presbyterian.
Me: We haven't really made any solid plans for where we're having the ceremony yet. We're trying to find food vendors right now, and they're all so pricey. Do you know any good food vendors?

Kind of trying to organically change the subject like that.

She tried to dig in with religion multiple times until I was finally like, "Hey, I'm not really that religious. I don't really like talking about it because I don't really know much about it," or something to that effect.

She told me I needed to learn more to get myself "right with the Lord" and I said she was probably right, which seemed to satisfy her. She seemed to drop it after that.

Later that night, we were all sitting in the living room and I was working on a Biology assignment that was due in a few days. At this point, my future sister-in-law had joined us. Future mother-in-law glanced at my textbook then said, "Evolution is a load of crap. It should be illegal to teach that stuff." She said this with a tone, like she was trying to start an argument with me. At this point, I was over it, and said I was going to go to bed to work on homework and left the room with my textbook and laptop.

Am I the asshole?

going to bed when future mother-in-law irritated me