No sex life

I am sure this question has been asked a million times BUT...
I am 51, my husband is 60, we have no sex life. He has no interest what so ever in sex. We live like roommates, except we sleep in the same bed. This is not mine nor his first marriage and I do not want to divorce at my age. Him, I don't think he cares. "I don't need anybody" has often been expressed by him. We have only been married for 4 years (Been together 8). He discussed his decreased interest once with his doctor a few years ago. We don't discuss it at all, I can't even begin to think of a way to bring up the subject.
My husband was physically abused as a child by his father (his parents are both deceased now), so I am sure there are emotional scars there.
We are older, so neither of us have perfect bodies...Although lately I have been dieting and loosing weight. 5'1" 160 at my highest now 146, with a goal of 120.
My husband is also over weight, keeps starting and stopping as dieting, no will power it appears. He is not in my opinion ugly with the weight gain. 5'8" 200
from about 179.
Anyway, I am looking for advice on what it is I can do to try and 1) get up the nerve to talk about this with him, 2) finds ways to elicit and interest in sex from him 3) any advice at all.

Thanks
T