Marriage counseling only works if there is 100% transparency, no active affairs, and both parties are committed to the marriage. Ask yourself if those things are all true. If they are then go for it. As for an affair. How guarded is she with her phone? Next time you're going away from the house together purposely leave your phone at home. While you're out say "shoot, I need call _________ and I left my phone at home. Let me use yours." If she hesitates to hand her phone over even for a second then there's an affair going on. I wish that weren't true, but it is. I've lived it myself and I've seen it a hundred times on boards like this. It's a quick and simple way to learn the truth.