Boyfriends mom drives me crazy!

My boyfriend and I have been together for almost 3 years.  (He's 18, I'm turning 18 in a few months) And we have been together through hell and back.  We were best friends for years before we got together and I love everything about him.  BUT HIS MOM.  Girls.  I just can't handle it!!  I have gone through A LOT with my mental health and I've never had my families support.  But my boyfriends mom judged me for it!!  She knew so little about me before we met and she was so rude to me and literally acted like it didn't exist!!  (I would say hello and she would look away.........  Like ????) And they did a lot more damage than that of course.  (This post would be a million pages long if I continued on that.) When I'm gone, she says that I'm pretty and what not to my boyfriend so he never thought there was a problem.  His parents just don't mind their business, they're rude, they're cocky, they don't care about anyone but themselves.  At first, I didn't think anything of it.  Then I got really mad.  And now I try not to care but it's sooo awkward anytime I'm at his house.  I've always tried to be the bigger person but I just can't stand them.  I can't be happy for them, I can't talk about them, I can't be around them.  I just can't!! :/
Have you girls been through anything like this?  How do you deal??