Help Please!

Ok, so today I get an email with a receipt from Apple iTunes for a ringtone purchase. The receipt was for a country artist song that is highly sexual and suggestive in nature. I read the lyrics of the song and the song is discussing a man and a woman having an explosive love encounter and experience. Why does this matter you ask? Well, my W only buys ringtones when she is going to assign it to the phone number of a specific person. She is not a fan of country music and I know darn well the song is not intended for me. Well today we were talking on the phone about business and money matters, how are we going to split the bills etc. and I ask her about the song. Her whole mood changed and she got really upset and snappy when I asked her about the song. I probably should have not asked the song because I know why she has the song but I couldn't resist. I wanted her to be aware that I knew. It seems that she forgot that I get emailed receipts for song purchases. It's the little things that always catch people up in their lies. Needless to say I got a notice that she removed herself from the family iTunes music account after we got off the phone. Should I have left it alone or was this a good way of putting it out there to her that I know what the deal is? Of note, my friend from college and his wife are having a scheduled delivery in Dallas this weekend. She asked her parents to watch the kids because "we" would be going up there to see them. But then she goes on to tell me that she is driving by herself and staying in Dallas alone the whole weekend. I called her bluff on it. I told her not to worry about going to see my friends on their special day. I told her that they would be suspect of her being there "alone" without me. I do believe she was going to see them but I think she was going to use the time to also be their with the OM. She got even more upset and told me "that's fine" and that she "still won't be home for the weekend" and the kids would be in San Antonio with her parents. This adds more to my belief about her linking up with someone else.

Do you think I'm wrong in my position?