Am I wrong for letting my teenage son be naked when family is around?

My in laws have been staying at our home a lot lately. I've spoken to my husband about it because I really don't want them over all the time. I'm saying almost everyday and they just decide they can spend the night but he allows them. I have a son from another marriage who is 15 and we are going through a lot with him mentally and physically. He needs a kidney transplant and has been on dialysis for a month now. He's also bipolar which comes with it's own issues. My in laws have been over staying in our home for 3 weeks straight and I'm honestly getting overstimulated by it. My son was going through depression and having really bad pain. He was crying in his room both from depression and pain and hadn't showered in a week so I helped him to the bathroom to help him bath. He was crying in the tub and didn't even want to put clothes back on so I just put a towel over him and led him back to bed after his bath. When I come out my MIL starts losing it because apparently she was in the hallway with my husbands cousin when he came out the bathroom. It's not like you could see anything. He was completely covered in a towel and I was practically having to carry one side of him to get him to his bedroom. She said that's disgusting and disrespectful when there are house guests. I said this is my house and they didn't even see anything. She said the point is he was naked under that towel. My husband took his mom's side and said I can't let my son do whatever he wants because he's sick and feel like that whole family is ganging up on me. So was I wrong.