Unless your wife is extremely open minded about sex I wouldn't bother taking her there. She may well give you the impression she is cool with what you have done in Thailand and what goes on there but the reality could be something very different. In my experience there is only a tiny minority of Western women that can deal with Pattaya and the chances are that you will row with her when you go there. How will she cope with women blatantly flirting with you and coming onto you irrespective of the fact you have a girlfriend in tow? Throw alcohol into that mix and you have a recipe for disaster........you'll probably find that you'll spend a lot of the time rowing with your girlfriend when you should be having fun, hell, I row with my wife every time we go Pattaya...... and she is Thai! You know yourself that there is so much temptation in Pattaya and you'll probably want to sneak off to do something, not to mention the fact you'll probably be thinking about that hot girl you walked past in Soi 7 when you fuck your missus at the end of the night.
I remember when I was planning a trip to Thailand with friends many years back when I still hadn't been there and the plan was to take my then girlfriend there with a group of lads that had already experienced Thailand. Looking back I can't believe how ridiculous this now seems and I often wonder how many days we would have lasted before we would have split up had we gone ahead with the trip! If you love your wife implicitly and have no doubt you will stray then go for it but if there is even the slightest doubt in your mind then I wouldn't bother, you know as well as I do what it is like in Pattaya.