Anniversary ring or new engagement ring?

My husband got me a beautiful tension set titanium diamond engagement ring when we got married 7 years ago, and no wedding band. Although I absolutely love the ring, I have always wanted something bigger and with a wedding band. (the diamond in the titanium ring is small I think it's 1/8th carat) Every time I bring it up, which I only do near our anniversaries, he gets upset and I have to drop the subject. Don't get me wrong I LOVE my ring but there is no way to get a band with it because the band is so thick, my fingers aren't long enough for another ring in addition to the first one. My question is should I save some money and ask for a new wedding set (including a new engagement ring) or just get an anniversary ring? I dont want to hurt his feelings but I have always wanted at least a carat for my engagement ring.