My wife is with holding .?

My wife of 6 yrs. is starting to use as an manipulative "tool" to get me to "change". She's basically cut what little ual relations we have to practically nothing. Our regular encounters were around 2-3 a month, now it's more like once every month (34 and counting). I've been really thinking about getting a girlfriend or something but I really don't want to go that route. This has been going on for around a year. She's NOT going thru menopause or sick or anything like that.l