Mom's in a nursing home and a man that visits his wife in there is advancing towards my Mom. What can I do?

My mother considers him her boyfriend, even the nursing home social worker had concerns and met with me to address this because this man has done this before there. My mother has dementia and she was incapacitated but i thought to have her capacitated because her meds seem to help. Now she is hallucinating again. The social worker suggested she be incapacitated again. We talked for almost two hours and a week later i find out the social worker is helping her into low income housing with this same man. I am furious! There is much more to this. I just can't believe this man is allowed into a female room, i have seen him in the everytime i go there. He had even seeked me outside near my home to tell me how he loves my mom. She also just recently lost her husband my father who i cared for at home while she has been with this other man. To a point yes I'm angry for personal reasons but that is besides the point, this is wrong, even the social worker was concerned enough to meet with me about it. I don't know what to do, my mother can not even walk, she is mentally unstable, bipolar.. she can not live with this man nor live alone. I think this man is after her money, i told the social worker this also.i an appalled that this social worker is supporting this relationship and helping them be together. Please help, what can i do???

mmental illness