what i am feeling and why

Day by day goes by, the same routine, mostly housework and caring for the children.When I look at the relationship with my husband, its just all become so cold and routine too.He once told me it was all up to me to make the relationship better. I lost interest in sex and my depression just keeps me flat, spiritless in this body.  I always hug him and kiss him and I am affectionate as he comes in the door and leaves. I have his dinner on the table. I do what I am supposed to do.   He is so involved in his own life, working, going to college, guitar mass, fixing up the house. We don't and never have spent special time together. After awhile, you just accept that you don't have the money for rendevous and play your role as mother father husband wife.  I don't have a sex drive. When I was playing on the internet and being creative sexually, it all got out of hand, i felt sick and scared and just decided my life is happier without sex. My body is falling apart, I don't feel sexy, and I just feel depressed.  I know I was into sex more than him in the beginning, and since my fantasy life died, there is not much left in the bedroom.  I never thought in my whole life that I would be 50 and not want sex anymore. Nobody would believe this is the same me. I am not who I was and I don't like who I am now, just feeling old and useless