how to prevent music on iPhone from automatically syncing songs to iTunes I've created an iTunes library - around 1000 songs. My wife has an iPhone and has downloaded her own music to it. She recently connected the iPhone to our home computer (where my iTunes library resides) and all of her music was automatically added to the iTunes library. However, our music tastes differ considerably. 

At this point, what's the easiest way for me to remove her songs from the library? I can go through and delete each song, but I believe if she ever connects her iPhone again, it will delete the songs off of her phone too (or sync them back to iTunes). Is there some way for her to have her own library that she syncs with and a separate library for my music? 

I suspect this is a pretty basic question with an easy answer, but would appreciate some help.
Plug her phone back into iTunes. In iTunes, click on her iphone, and in Options uncheck anything having to do with "Syncing Automatically". If it's not already checked, click "Manually manage music and videos". 

If you want her to have a separate iTunes library, she should also have a separate login for the shared computer. This is really the easiest way to deal anything on a shared computer.

Incidentally, there shouldn't really be any reason to physically plug your iPhone into your computer anymore. You can actually set the phone (and iPads, etc) to sync wirelessly.