My boyfriend(23) and I(23) are high school sweethearts. After leaving for college, we agreed to move back in with his mom (MIL 49) to save for a house. We've been extremely disciplined, avoiding outings, drinking, or partying—every cent goes towards our dream of owning a home. I've wanted my own space since elementary school due to a tough family background.

My MIL has been single since divorcing 20 years ago, and my boyfriend naturally became the 'man of the house.' He enjoyed helping out, so it was never an issue. Now, we've saved enough for a house, and she knows it.

Since learning we plan to leave, she's become distant, speaking to me only to say 'good morning' or when she needs something via my boyfriend. She stopped offering me things and became noticeably cold. I tried addressing this, but she wouldn’t engage. She’s also stopped cleaning shared spaces, though I let that go since it’s her home.

The real shock came when she told my boyfriend, knowing my lifelong dream: 'If you don’t agree to a multi-generational house, I won’t be able to afford living in my own home anymore. And I could give you the money I promised you by selling the house.' This, despite us giving her only $100 a month."

Mind you she doesn't respect our privacy. She is constantly asking my boyfriend where he's going, calling him when he's home late (despite him telling her he didn't know the time he would come back). She's constantly making comments about the neighbors, looking at what they're doing, etc.

My boyfriend tried to set boundaries with her and talk about it, she listens for a few weeks then goes back to her previous behavior.

She practically let me live with her for free and is a nice person other than all that.

So, would I be the AH for saying no to her?