So OK, a bit of a 2x4. You feigned interest in your S3 in order to try to ascertain if he was at OM's or MiL's?
You realize this is a no-no.
This is why you need to be careful about how "over" everything you really are. We've talked before about how you have no control over where she stays even with S3. Unless OM is a sexual predator you have no legal standing to demand she keep S3 away from him.
You can scream, yell, jump up and down, hold your breath, stomp your feet, etc.....you have ZERO control over that.
So concentrate on what you CAN control, and that is sending premeditated texts to your STBXW in the guise of asking about S3.
M(53), W(54),D(19) M-23, T-25 Bomb Drop - Dec.23, 2017 Ring and Piecing since March 2018