‘Having a lover might solve your sex drive but so would a vibrator.’
Ask Santa to drop one into your husband’s Christmas stocking. Take it from there.
If your husband, with all your shared years, cannot see the love, affection, humour & invitation to play behind this (even if you become the only user of the toy) , then you both really need to talk about what’s next in your marriage.
Before your relationship falls asunder, try everything reasonable, e.g. couple counselling at Relate, you can do together.