MIL constantly comments on my size

At my baby shower, my MIL said repeatedly “I can’t believe how huge/big you are!” No less than a dozen times. She also told my own mother how she couldn’t believe how big I’ve gotten repeatedly. I thought my mom was going to strangle her! I’ve only gained 15 lbs at 30 weeks and every other person there said I barely look pregnant. I know this is just her social anxiety and repetitive talking style, but I honestly don’t know if I can make it through thanksgiving with MIL. We’re spending three days at her house…going to be a long weekend.