Many asexuals do have open or poly relationships though. It's as varied as any other orientation in that. Some prefer monogamy, some prefer poly, some are indifferent and go with whatever their partner wants to do. Some can have sex, some cannot. Some can enjoy sex, some cannot. The main difference is lack of attraction and/or desire to sex - so that urge the OP describes "doesn't that make you want to have some playtime in the bedroom?" - nope, nothing ever has made me feel that way. Sex is something I have to actively remind myself about my partner probably desiring if I say or do X thing. It's just not something I find natural to think about or do for me (I am not saying sex is unnatural, I support people having whatever consensual sex they want). And I have NEVER thought "Man, I wish he would make love to me" (or anything like it) when looking at someone, like my friends and family say about actors and such during steamy sex scenes on TV, or trying to pick up one night stands.

Anyway - I don't want to get this thread off topic. I just wanted to put out the minority opinion that : Yes, people really can simply not want sex and it have absolutely nothing to do with the relationship being "bad" for them or them not being satisfied with it. It doesn't mean the person that wants sex has to just accept it and do without something they find important. If that becomes an incompatibility that cannot be handled, then there is no shame at all in admitting you need something a partner cannot give.
So, if the OP is unsatisfied with his sex life, that is certainly something to discuss. But, if his wife has NEVER had much of an interest in partnered sex, there is a pretty good possibility she isn't going to suddenly get interested. Especially if she's already enjoying it physically and still has little interest. There is a possibility of hormone imbalance causing low libido, but her libido seems fine if she's masturbating regularly. From the information given, it seems she just prefers to handle her libido herself most the time. And I know a lot of people who have been like that their whole lives, some of them even 60-70 years old now, who have had batteries of tests trying to figure out why they were like that, with nothing showing up abnormal. Not all of them identify as asexual, since some don't feel it all fits them - which is fine, no one has to use any label they don't feel fits them or don't want to use. Some call themselves "grey sexual" because they enjoy it and maybe even want it occasionally, but just don't care all that much about it and it frustrates most "average" people since it's a different sex drive than the societal norm. Some call themselves "demisexual" since a person that sparks their interest in partnered sex is once in a blue moon and it may or may not spark with someone they fall in love with and even marry. And some just use heterosexual or homosexual or bisexual or pansexual and give their partner an explanation of exactly how they feel about sex before a relationship to avoid any misleading.
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