whats wrong ? why doesn't my husband want sex???

I Just finished up a psychology class and i learned that as men get older, it is harder for them to reach a full erection and keep it. They need more stimulant and this is usuallly where porn comes in because it's something graphic and something new for them to see. i doubt he isn't attracted to you anymore, he is just at the age to where anything sexual has to be carried out farther. I'll give you some suggestions.
try giving him a little strip show, put on some thing sexy, put on some good music, sit him in a chair and strip for him. if you really wanted to spice it up, set and chair infront of him and let him watch you masturbate. Now this is next part is very important, it is a proven stufy that men are more aroused when a woman moans during any sexual play.
If that doesn't work, get him some viagra.

My husband and I have been together for 7 years and married for 1 year. 

Since getting married he is totally NOT interested in having sex with me...Ive let it ride and put it down to what he calls 'being tired'.

The other night I tried to initiate it in bed, I thought he was all excited and up for it until he said one second I need to pee, so there I lay in bed waiting for him to get back and jump on top of me, but he just rolled into bed and said you sound tired, I said Im not, then he said well Im tired.  So again I just rolled onto my side and closed my eyes fighting back the tears until I finally fell alseep. 

I dont know what to do, Ive tried to make an effort in my appearance.  The only way I get anything is if I pleasure myself!

I dont know what to do anymore...