Sweetbriar, you'll get through this, it just feels horrible a lot of the time. We've all felt it.
Try not to worry so much about what OW may or may not do in relation to your H. This is not a competition, don't feel that you have to "beat" her at being H's partner.
Stand strong.
Me 57/H 58 M36 S 2.5yrs R 12/13
Let me give up the need to know why things happen as they do. I will never know and constant wondering is constant suffering. Caroline Myss