I Am Torn Between My Husband And Mom ,what Should I Do?

Your husband is being very selfish.  As a mature adult he should realize that your mother needs your assistance right now more than he does.  What does he need from you that is so imperative?  His dinner cooked?  His laundry washed?  Come on, your mother just had back surgery, certainly that's more important.

You should let your husband know how you feel and if he truly loves you he will understand your choice by helping your mother in her time of need.

You will only ever have one mum.  She nurtured you and loved you for who you are.  I lost my Mum 14 years ago and I still miss her so much.   My advice would be to stay and take care of her.  There is not one day goes by when I would give almost anything to see her even just for a moment.  To see her smile however briefly.   Your man may love you, but to be honest just how much can he love you if he is giving an ultimatum.

Who really needs you the most at this moment in time?
Assuming that your husband is able bodied, he should be able to cope without you for a while.
How would your mom cope if you left right now?
I think these questions will help you decide.
They are both very lucky to have such a considerate person in their lives.

I say choose the one you have sex with everyday and the one u plan on spending your life with