I have been married 30 years. My husband doesn't understand why I, at age 53, don't get "into" sex the way I did 20 years ago. He watches porn every day and thinks I should be enjoying things like the people in the movies. I think he is desensitized.

Everyone ages differently. I'm 47 and as horny as I was at 16. My wife has lost a lot of her libido. Most men I talk to have the exact same experience. Perhaps it's a gender thing.

I have been married 30 and and a bit years and had gone right off sex (I'm a woman too). I know you will probably seem disgusted , but have you tried watching the porn too-? it actually makes me feel like having sex , so it works well for both me and my husband, because it's so much better if I feel like having sex, rather than it being like a chore for me. Maybe it's not as bad as you think to watch- it just helps if I'm aroused too, rather than just my husband!

Desensitized and also over-stimulated.
You are presumably past childbearing age and it is generally normal for women as well as men to think less about sex after the age of fifty. I think it is partly hormonal. If you always enjoyed sex with your husband you will usually continue to but will not want it as often.
As we go through life we are stimulated enough by seeing people every day and by thoughts we might have. Unfortunately TV shows, movies and even some music now and for a long time has contained a lot of sex and a lot of it might as well be pornography. I think that those things and real pornography artificially and unnaturally boost our level of stimulation until it becomes unreasonable.
I am a man ten years older than you and even I feel my level of stimulation increasing just reading the questions, answers, and comments on this web site. My wife is my age and we spend a lot of time holding hands and enjoying each other's company, shopping together, taking walks, etc. We enjoy lovemaking maybe once every two weeks or so. I am not saying this is normal but as a young man I remember with wives and girlfriends wanting it every day or sometimes a couple of times a day (I did not know my now wife then).
So I think that pornography of all kinds is too much for people, and I agree that too much can be desensitizing - it makes us want more and more and we lose the simpler but greater pleasures of touching our partner's body, listening to the sounds they make as they enjoy us, and other things associated with our natural desire for the man or woman we are with.