Kwandoku, we usually warn newcomers that are sure their WAS has no one else to brace themselves. Either they really do or there is one waiting in the wings, or the WAS is on the prowl for one. However, it doesn't change what you should do much.
One thing it does do is requires no sexual contact between the two of you. Don't put your own health at risk. Also, kick her out of the MBR. When she argues, complains, cries, asks where she should sleep, etc, you stand firm. That is not your problem. Your stance should be that you refuse to allow a cheater to share the MBR with you.
Kwandoku, stay strong buddy. It will get better!
M(53), W(54),D(19) M-23, T-25 Bomb Drop - Dec.23, 2017 Ring and Piecing since March 2018