I (21F) get weird vibes from best friends (21F) fiance (30M); should I still participate in their wedding?

Best friend "Brandy" and I have been close since elementary school. We have a very close friendship, and shes truly my sister not just my best friend. She met "Daniel" (30M) when we were about 11 and he was 20 while he was volunteering at our school at the after school program. She had a crush on him from the start and they flirted a lot which always made me uncomfortable because he was so old. We stopped going to after school in 6th grade and didn't see him until our freshman year of high school, where he worked as a tutor. This time they started legitimately dating despite it being illegal in many ways, and Daniel came close to losing his job at the school because rumors started to spread. I finally confronted Brandy on the situation and told her that it was weird and inappropriate, and we fought so hard that we didn't talk for nearly a year.

We reconciled after they broke up and he quit his job, and to my knowledge they didn't talk until last year. Sometime last year they started talking again, and now have been dating for 6 months. Brandy told me last week that Daniel proposed and that they'll be getting married in November. So many things about their relationship worries me and sets off red flags, and the fact that Daniel is pushing a wedding and they're trying for a baby is not normal.

I've been on double dates with them a couple times as well as had them over to my apartmemt and the way Daniel acts towards Brandy is creepy to say the least. If me and her are having a private conversation he has to come and butt in and harass her. If we're in the kitchen getting drinks or snacks for longer than a minute hes calling down the hallway "babe, what're you doing in there?" He makes fun of her and tries to scare her, but she assures me that that's just how they play around. Hes very condescending and comes off as controlling; a lot of the things Brandy and I used to do like going on late night walks for slurpees or night drives to the beach is now off the table because Daniel doesn't like it. He has at tracker app downloaded on her phone that she has to keep on and of we go somewhere he's blowing up her phone asking what shes doing there, which means when they're apart hes constantly watching her. Hes constantly nitpicking stupid things like mismatched socks or lipstick on her teeth and calling her immature. Hes never been explicitly mean, just weird, and I worry that him pushing marriage and kids so quickly is because he wants to lock her down before he shows his true colors.

I don't like Daniel, and I'm concerned. I worry that if I say anything to Brandy or bow out of the wedding we will never talk again, and that worries me because I'm pretty much her only friend and she isn't close with her family so if he becomes abusive she'll have no one to turn to, but i feel like by participating in the wedding I'm endorsing this weird relationship. What do I do? Should I pretend to be okay with things so I can continue being there if she needs me? I've read a lot about abusive relationships and I know that if I'm a threat to Daniel he'll convince her to cut me off, and if things get bad I don't want that to happen. What do I do?

Tl;dr: best friends fiance creeps me out and seems potentially abusive. Should I stay in the wedding party as the maid of honor or bow out because i don't agree with their relationship?

Submitted April 30, 2019 at 12:35PM by bluedogpaw http://bit.ly/2UPkUm2