Dazed...If it were me I would do the "right thing" even if my spouse was not...I would unfriend those of the opposite sex if they were not mutual friends to both me and my spouse...I would be transparent even if my spouse didn't want to be because it is a way of putting the glare back on them, if you have nothing to hide then why try and hide???
As for what to do when she makes these accusations...the DB way would be to stay calm, not throw back accusations(even if justified), and simply state, "I am sorry feel that way. I simply have no romantic interests outside of this marriage." End of discussion!
There might be a more clever spin to put on that but I was not overly good at "clever" when I was in the midst of my H's MLC...being with someone in crisis brings you into a crisis too, like it or not...
You can't make your wife do the right thing, you can't make her believe what she doesn't want to...but you can do the right thing and know that you are not in any compromising situations...self-worth is very valuable in my book...it is what brought me through a lot and as odd as it sounds it is something that my husband now values very much in me...if I stood for the right thing when he was doing everything wrong why would have room to question now that he is doing the right thing?...It has made our relationship stronger...