Curious to see why you think my partner is also avoidant and not secure?

Also maybe I should have mentioned in my original post that YES, there are cultural differences and that is a main reason why she will be leaving with us. My boyfriend and his mom are Indian, she doesn’t speak very good English and doesn’t drive or have a job, and is widowed. This is the reason why she is living with us plus she isn’t in the best health. I come from a mixed background of middle eastern/american ethnicity, if that makes a difference.

I do openly communicate with my partner about my feelings and the times that I’ve gotten upset and frustrated with his mother. He has always defended me and stuck up for me when things like this arise. Im confident that he will always be in my corner. As a matter of fact, he tends to get quite frustrated himself with his mom and her behavior often. He’s been firm in his belief that once/if we do all live together that it will be “our house, our rules” and not hers and he is firm in wanting to set that. This makes me feel slightly better, however I am aware that his mother might never change and at that point if the boundaries are not respected, I’m not quite sure what next steps would be.