Am I having back or white thinking about relationship with insufferable MIL

This one is long, just a warning!

For context on my MIL, she is a conspiracy theorist type. Examples of things she's said/talked about: Anti vax,chemtrails, the govt knows our thoughts, I can't lose weight because the govt is poisoning me, everyone should fast for a week to lose weight, eating disorders, diet cures autism?? Any time I see her, alone with my son, she only talks about these things and herself. It feels like someone is sticking a straw into my barely full cup (I'm a FTM to a toddler so I am exhausted a lot) and gulping out of it. I am just exhausted after interactions with her. You also can't disagree with her or else she loses her shit.

Ok so here's where I'm lost! I got into a huge argument with my husband last night because I had been having anxiety about seeing his mom and finally decided I'd only like to see her when he (my husband) will be around. She tends to be more chill when my husband is around because he does not give a rats ass about ignoring her. I don't confront her because I think I'm just non confrontational and I know she gets that, hence why she only says outlandish shit around me.

My husband says I'm having black or white thinking by saying I only want to see her when he's around. I've made it very clear over the years that I am not interested in her crazy theories because they're all shit she got off Facebook and there's no evidence to back it up. I just say "wow! That's crazy!" Or "wow! I'll have to look into that" If you have ever been in a situation like this, how did or would you handle it?

I'd say 95% of mine and my husbands arguments are about his mom. She's constantly making weight comments about my husband and I, saying "I can't wait to show you the 'truth' of the world" to my 16 month old son???? And constantly making remarks about my son when he's having a hard time or throwing a tantrum because he's teething a lot right now. She always says "wow! What a drama queen!" Or "My kids NEVER threw tantrums!"