I agree with Lilith, and I agree with sixsense also.

If you try to find someone without paying for it (via online, etc.) then you run a HUGE risk of it blowing up in your face, trust me on this one. Its really hard for women and men to have sexual relationships without emotion, no matter what anyone may say. Some sort of emotion will come into the picture eventually, especially with the sort of session that you are planning on having, and then you will be in big trouble.

On the other hand - you love your wife and all, but if you loved her so much wouldn't you take the time to talk to her, get some help together, try some different things, before having an affair?

Just make sure the affair is what you want to do. Affairs can get extremely complicated and messy - and your wife will have some idea that you are getting it somewhere else, no matter how much you try to hide it.

If you still want some go for it, try an online dating thing - I think that is the best advice.

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Would you like more sex with that?

I wouldn't recommend sex, drugs or insanity for everyone, but they've always worked for me.