If you get a full length one I don't think she would be able to tell its for compression. If your getting it from underworks its got a mesh-like feel to it so its not gonna feel like a regular tank top but they are the best in my opinion. Also the ones from underworks it has to be washed in cold water and with no softener. I just wash mine in the sink because it helps it last longer, so you may not even need to have her wash it or even really know you have it if you wash it in the sink. Congratulations though, its a liberating feeling to put on your first binder and look down and see nothing there