Sorry to say that some partners in stable relationship still does such shameful thing. Am sorry you’re going through these issues with your partner its shows that your partner isnt ready for a committed relationship and still wants to see what else is out there. But the question is should you leave now or still hold on?.
I don’t think there’s a right or wrong here. If you are getting something reasonable from hm/her or on the other hand you will be putting up with what you say is “eating your alive”.
Just ask yourself those following questions: Are you being honest with yourself? In other words, if you stay, do you hope it will buy you time and maybe you feel he/she will change? I’m sure you realize that’s highly unlikely, but you may be hoping against hope that he/she will. Are you prepared to find out even more of your partner secret activities? Are you sure he/she will even give back something reasonable?
However, Just be true to yourself to make the right decision and you can move on with your life.
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