So I share a lease with my sister’s wife. We live in a 2 bedroom 2 baths for $1344. She has a huge room, with a walk in closet and a bathroom in her room. When we first moved in I wanted the bigger room and I was willing to pay more for it, she and my sister wanted it because it was going to be the 2 of them with their son so they wanted it and wanted to pay more for it too. So we agreed that they would get the bigger room and pay more for it. Now my boyfriend stays with me, its been about a month since he’s been living here with me and they want us to split the rent in 4. My room is tiny and so is my closet, mine and my boyfriends clothes barely fit, my bathroom isn’t in my room so everyone always uses it and always takes my toilet paper etc. (Totally different issue) They pay $200 dollars more for the room so I pay $472 and they pay $872 and now that my boyfriend is here we split the bills in 4 instead of just 3. My boyfriend stays in my room all day, we never go out to the living room and we keep to ourselves, we buy our own groceries, never touch anything that’s theirs (they always take my toilet paper, shampoo, I buy groceries regularly and they buy very rarely) so I don’t think we should being splitting it in 4, it doesn’t seem fair to me. Am I wrong?

Just some background info: My sister’s wife moved in her sister’s family and our rent and bills stayed the exact same (it was her sister, her sisters bf, and their 2 kids). They were here for 2 months and I didn’t say a thing other than all the noise it brought, which I probably should’ve, anytime I tried to they said they were living in their room so it shouldn’t be a problem. I feel like it shouldn’t be a problem if now my boyfriend is living in my room then right? I don’t know

Any advice is welcome, on the rent and how to make this work. Our lease will be up in ma