mother in law? overprotective of her son? (kinda long)

Cheyenne ✊🏿
Does anyone here do their best to treat their spouse's mother (or father) with respect and genuinely try to build a relationship with them...but still gets little sneaky sly slick shit subliminally thrown at them? 
Something was said to me and I thought (my naive self) that I was having a genuine heart to heart with this lady, (my boyfriend always encourages me to talk to his mom because my mom and I don't have the best relationship so it's been hard, but now I'm to a point where I feel a little more comfortable) I told my boyfriend what was said between his mom and I because earlier me and him had the same exact conversation, and he confronted his mom regarding something she said that he felt wasn't true and boom...a huge argument ensued I didn't mean for there to be an argument but now I know how she really feels and this is one of the reasons why I explained to my boyfriend that I don't get close to people ,I don't even have a close relationship with my own mom so building one with his was already a hard task but now? I'm done I see the fuckery clear as day! The ONLY reason why I went back to my boyfriend was because I told his mom about the conversation me and him had so then I told him about the conversation me and her had ( maybe I was wrong but I had no ill intentions I was just speaking on the situation at hand and genuinely talking about it) my boyfriend then (in the middle of arguing) said any woman he has ever brought home his mom was jealous of or feeling like she was losing her son, it's like Norma from bates motel 😒🙄 don't get me wrong she's a nice lady but she won't let her son grow up! And I'm officially over it, even when he moved out of her home she told him she's his comfort zone and why would he leave her and he's gonna be back mark her words...
Now I'm like I'm done, my baby will be here in September and of course she's a grandparent but I have nothing to say to this lady!! Am I wrong!!? 
P.S WE ARE VISITING HERE ON VACATION, WE LEAVE TOMORROW (THANK GOD) this lady came upstairs and apologized and said I didn't mean to hurt your feelings that wasn't my intention, I'm happy you guys are here but I'll be happy when you guys leave too(I wanted to snatch her scalp!) how do you apologize but still throw salt!!? It's FAKE and I've never been one to disrespect anyone or their home but this lady really really upset me because of her twists and lies she then tried to say I ASKED HER her opinion on me and her sons relationship (which is a damn lie) but I don't wanna say anything because I know I will argue with her and I don't wanna disrespect anyone's home