It really doesn't matter what anyone else does. It matters what OP and her husband do. He is plainly not happy with the situation and he shouldn't have to pretend he is just because some men like bankrolling a woman who does nothing except make dinner and paint.
Regarding the issues with intimacy (ten years without sex, a no brainer), the problem with people who refuse to have sex with their partners is often not so much the sex. It's the fact that the refusing partner just doesn't give a monkeys about the effect on their spouse.
I think a lot of people could probably get by with little sex if they still got lots of intimacy in other ways, reassurance that they are loved and wanted, and the reluctant partner actively sought help - and worked with the therapist - to try to fix the issue. In other words, acknowledged how unloved, unattractive and unwanted their partner would be feeling, and proving through actions that they cared about their feelings enough to at least be TRYING to resolve the issue.
We don't know OP, true. But there is nothing, in this thread or her other one, that suggests she values her husband as anything more than a cashpoint who should also still parent their teenager during the working week when it doesn't suit her, a SAHM, to do it.
She has not, to my recollection, mentioned the sexlessness before now, which implies that she didn't think it was a problem until she discovered the affair. Actually, she still doesn't think it is a problem because she's still claiming she's done nothing wrong and shouldn't have to make any changes.
How self absorbed can you get? And now she thinks that because her husband took up another relationship because he frankly didn't have one with his wife, she is the permanent victim and should not have to make any changes at all?