Two women in one house

My husband is on deployment and will be returning in July. We recently had a newborn in March. His mom will be coming to USA(we’re from the Caribbean) to work. My husband and I decided that she’ll be residing with us until she can “get on her feet.” Now he changed his mind and wants her to live with us permanently. I’m not with that. Ever since then, he’s been quite disrespectful. Ever since he began to work, she’s been fully dependent on him, even though she’s married. She’s an adult, pretty much young (39years old), not disabled, not sickly. I believe she should be independent. I’m willing to help her as much as I can( found her a job, opening my house to her temporarily.)

Am I wrong for not wanting my mother-in-law to reside with us permanently? Am I “undermining” my husband? Am I being ungrateful?