We had relatives stay with us for a while and it wasn't an option for me as she dropped the bomb then. I didn't want to create a huge scene. This is before I discovered the DB forum.
Are you willing to take it back? Since she is cheating on you I would not only suggest going back to the MBR but letting her know she is no longer welcome in it until she proves she is not sleeping with OM.
M(53), W(54),D(19) M-23, T-25 Bomb Drop - Dec.23, 2017 Ring and Piecing since March 2018
