Not sexually attracted to hubby anymore but love seeing him with other women

I need some advice or support in this matter.... please be kind. Me (F45) and hubby (M49) have been together for over 25 years, married for 13. We have been in a semi-open relationship for 10 years. We classify ourselves as swingers. About 5 years ago, I noticed that I am not sexually attracted to my hubby anymore. I blame his lack of self care where I am doing everything in my power to remain healthy and fit. Hubby has developed a huge belly, diabetes, cholesterol and high blood. I love him to bits as he is like my best friend but I do not want to have sex with him anymore yet I like him enjoying himself with other women. I wish he could enjoy seeing me with other men but he does not like watching me or finding out details. Our marriage is heading into a rift now because I refuse to be sexually intimate with him. I do not have a problem with him being with other women but it is very rare but accepts (does not like) me being with other men which happens far more than what he thinks. So my question is, what do I do to fix our marriage when I want him to enjoy seeing me enjoy myself with other men?