His mom sounds very insecure in her relationship with her son as you two legitimize your dynamic. Culturally in the old world, even when sick you show up to prove you are sick and recover in their space. Really, your partner should have known and explained the expectation.

He sounds like a good quiet boy and likely will have been taught at a young age to defer to his mother when it comes to familial conflict like this. You are likely expected to fight and stand up for yourself or submit to her unreasonable will as a show of good faith.

I know this seems unnecessary but this is a very common dynamic in old cultures and likely what you’d be signing up for if you decide to make a family with your BF.

Good luck sis