i do think it's disrespectful of her to speak with OM under your roof. you might consider making this a boundary of yours. and are you paying for this cell phone she uses to call/text him? cancel it and make her purchase her own. search for chocolateyes threads - he 'manned up' and did this, not rudely, just from a loving firm place that would not be disrespected any longer.
and get back in your bed. she's cheating, she can move from the marital bed. JMO. easier said than done, i realize.
Forget the former things; do not dwell on the past. See, I am doing a new thing! Is 43:18-19
If it seems slow in coming, wait. It's on its way. It will come right on time. Hab 2:3