There's an old saying. Men usually addicted/obsess to at least one of the following issue:

Money, Sex, Gamble, Lazy and Drug.

Personally, I believe in this. You need to find what's your husband obsess which above. No married men will denied sex with their wife unless you are ugly, fat or kanasai type (see face also want to slap).

You had denied him 1 year without sex. Most probably he already found an alternative solution by now. You do know in Singapore is as simple as buy economy rice to get paid sex, right?

I'm not saying your husband 100% cheat on you. You need to check it out your self. Honestly, we men are simple/dumb species. If we cheat, we don't know how to hide our trace unless you met a PRO Player (which i'm very doubt your husband will be).

Read around this forum (or any relationship forum), you can see majority men complain about lack of sex because the their wife are tired, period, no mood/sleep etc.

Just test him, tease your husband when at home. semi nude in room or revealing cloth etc. This should turn on your husband if he is not distracted by other obsession's.

Another point you need to take note. Men can masturbate every day but not all men can have sex every day if they are not fit (if your husband above 80kg++).