How can I make my mom realize that I am her son and not her husband?

My mom often thinks my husband is hers ;-). We just don't kiss or hug in front of her or say lovey things in her presence. That allows my mom the ability to see me not as a rival. You may want to learn techniques for dealing with person's with demensia. Read and watch videos by Teepa Snow and Naomi Feil. Good luck

I'm in GA and work for a Medicaid Waiver program. I'm sure your state has one. The waiver I work for is Community Care Services Program (CCSP). In essence, the program is to keep people out of the nursing home by providing services to keep them in the community. If your mother is still somewhat independent, she may be appropriate for a personal care home. To be eligible, her finances will be looked at. Depending on her monthly income, she may or may not have to pay for the services. Call your local Area Agency on Aging to see what resources are available. Also Google "Medicaid waivers" in your state. Here's a bit more information on CCSP in GA. https://dch.georgia.gov/sites/dch.georgia.gov/files/16CCSP.pdf

There is no reasoning with dementia. You are not going to force her into thinking your way because she is in her own world. No sense in trying to change her mind, you will not win.
This situation is toxic for you and your wife. You, as the son and husband, are caught in the middle between your mother and your wife. Your wife will become more and more resentful with your mother's behavior putting you in the position of defending your mom. You need to get your mom the care she needs somewhere else. The most important thing (in MY mind) is keeping your marriage intact.

Talk to a hospital social worker for placement in a nursing home or board and care home. Check out the library for a booklet of seniors guide to services. As long as your mom doesn't have too many financial resources, she probably would qualify for Medicaid. You would need to find out what the monetary limits are. Call the Medicaid office in your area. Google senior services for your state.
Good luck.

Long term care would be the answer. Check into it. Is she on any meds to help with the delusions?

Would your mother qualify for Medicaid? That may be the solution to affording long-term care.

I'm not sure that there is a solution to her delusion about you. Do you sound a lot like your dad?

In general it is usually considered best to go along with delusions. I have no idea how that would be in this case. If you really were her husband, which in her world is absolutely true, then naturally she will be mean to any rival for your affection. What would happen if you starting calling her "dear" instead of "mom," and you referred to your wife as "Ms.Collins (that lady you hired to help with the cooking.)" I'm not recommending this, necessarily -- just throwing it out there for discussion.

Meanwhile, if you think long term care would be best for your mother, do look into Medicaid.

Your time would be better spent researching Medicaid rules for your state and finding LTC for your mom. She has lost the capacity to reason.
Medicaid is for those who don't have the ability to private pay. It's not your family's ability to pay but moms ability that matters. Read about the five year look back and make sure mom hasn't gifted large sums to anyone. Depending on her situation an elder attorney might be a good place to start to get the process handled.