His mum hates me!!

So I've been seeing this guy for about 7 months but we made it official a few weeks ago (I had commitment issues, the thought of being in a relationship freaked me out for a bit) but I've met his mum a few times before and after we became exclusive and she honestly hates me and it's depressing my soul 😅😩 she purposely calls me by another girls name... she comments on my tattoos saying people that get tattoos are seeking attention, she has little snide remarks to say like "I never would of imagined my son with a girl like you" or "interesting choice of makeup/clothes" she literally puts on the fakest smile when she sees me and has mentioned NUMEROUS times that I'm lucky to be with her son... and often says stuff like "what ever happened to Rebecca? She was lovely" (his ex) right in front of me ... I've mentioned it to my boyfriend and he just shrugs it off and says "I'm just a mamas boy she's just protective" am I overthinking?? Cause this is starting to cause a strain on our relationship 😔