If I were in your position I would ask myself one very important question -" Am I willing to be involved with someone who is bisexual." The point is that she is probably willing to be sexually active with any person of either sex of her choosing.You need to think this thru VERY carefully. The idea that you may be able to tolerate it is a bad idea. For this deal to work you need to be very comfortable with the whole scenario with all its potential rewards AND its pitfalls.If you cannot find some contentment and acceptance , walk away NOW!