Re-read the responses and you will see several people saying "you must tell" but none who say you shouldn't. Instead, you hear the experiences of others in a similar position, understanding that the details of your circumstances are unique and YOU are in the best position to decide if you should tell or not.
I like the spirit of this, adjusted to fit your situation. It's similar to how I told my wife, that is, easing into it rather than going all in all at once (like greeting her at the door fully transformed). My wife and I were in bed; she was reading a magazine article and I was watching TV. The article mentioned a crossdresser and she told me about it. My response was rather dismissive: "harmless fun". That started a conversation and some questions: "did you ever do it?" (yes) "did you like it?" (yes) would you want to do it again?" (yes) "THEN DO IT!" The next day I began to re-build my wardrobe and supplies. I was one who married believing that my desire for my bride would replace my desire to crossdress (so I purged). I was wrong, but it wasn't intentional deceit. Like many others, I found myself with an unintended potential problem: my wife doesn't know I am a crossdresser and I don't know whether to tell her or not. So I eased into it, trying to read her acceptance (or not) based on the conversation, and ready to shut it down if it didn't go well. If that had happened, I probably would have kept it secret.
It seems that the "must tell her" advocates usually leave out the possibility that your marriage could end, but even those who include it consider a broken marriage collateral damage to the greater good: truth.