I had the same problem. My daughter would frown up and push it out with her tongue. It took me and my husband 3 weeks of offering the bottle twice a day before my daughter would finally take it. I'm not sure how long you've been trying, but don't give up.
Make sure you're using one of the bottles/nipples that are designed for breastfed babies. These usually have a wider base.
If she is choking on the milk, check to make sure the nipple hole is not too big. I always use the slow flow stage 1 nipples--even now and my daughter is a little over six months old.
Warm the bottle nipple under running water before you give it to her. You can even try putting it in your shirt for awhile to make it smell like you.
Try making bottle time fun for her. Sing an upbeat song and act excited like she's getting a special treat. (This sounds kind of corny, but it actually worked for us sometimes). Give her the bottle when she's sitting in her swing or bouncer or something else fun.
Good luck and keep us posted.