Is loyalty important in marriage even if one of partner has health problems?

Yes. If they lose loyalty then, then where else will they lose it. They have no right to expect it in return. Yes, it's important.................

If you can't be faithful, you need to divorce. You are breaking the marriage contract by cheating. People divorce all the time, it's not a big deal. If you have a really good job, maybe your disabled spouse wouldn't care if you cheated. Some people don't care. If your spouse is very physically disabled, she might be too tired or too sick to care if you were having sex with other women behind her back. I would probably let my husband cheat on me as long as I didn't have to see him and her having sex together.