Urg yeah anything that goes near a mucus membrane doooon't share. I learned that the hard way; got pink eye from using someone else's eyeliner.
You might want to try buying your own. I use brown eyeshadow (a good brand usually... MAC but I like coastalscents.com too) as eyeliner with a brush. My skin freaks the **** out about everything, but that combo seems to be OK. Everyday minerals is good for those with allergies/sensitive skin because if I remember correctly they don't use bismuth oxide (unlike bare minerals) in their makeup.
Always make sure you have clean brushes/hands/face when applying makeup, because bacteria can make your allergies act up too. Or clog your pores, or get in your eye and cause an infection. Dirty brushes=bad juju.
But if you try your own makeup, and it still causes allergies, I suggest everyday minerals. I have it and I like it. It's fairly inexpensive too, you just have to order online.
good luck!!!