What you should do if he goes over there again is go with him. Hug him in front of her or slap his bum, get him to give you a kiss and see how she reacts. Just say the reason you are with him is 2 people can get more done than one. If he has to go again after that then make sure you always go with him. If you can't go for any reason then he cancels it. Or he can just block her.

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