Sex and Marriage

I am in my mid 40s and I have been happily married for more than 20 years. I have always had a very healthy sexual appetite and when we were first married every I was great. But about 5 years into our marriage my husband developed a chronic debilitating illness. He is often in pain and his libido is non existent. I love him so much ... but it is so hard on me. I find myself constantly fantasizing about sex with people I meet or interact. It is so embarrassing to even admit it. I would never cheat on him... but man I miss sex so bad. Anyone in the same situation? Any wisdom or words encouragement? I never thought my life would be this way !