You can absolutely tile your garage floor and your tiles will not crack under the weight of the cars or standing water if you do the install correctly.
However, if your garage floor is spotted with grease, or if the concrete was topped with a curing compound (drop a bead of water on it and if it absorbs, you are okay), you are looking at a much larger project than an epoxy floor. Ditto if the floor is out of level.
If your floor is grease-free, unsealed and reasonably level:
You will need to begin with a porcelain tile rated for exterior (99.9% of porcelain is) and a PREMIUM thinset. Better still, you'll want to apply an anti-fracture membrane to the floor and , as "Lady" mentioned earlier, consider locating "soft joints" or expansion joints every 8-12' of the surface and around the perimeter to permit the natural expansion and contraction caused by cold weather.
The cost of the tile should run between $2-5 per square foot and the thinset + anti-fracture will come in around $2 per square foot.
If you have more questions, you can call the tech service number of any thinset mfr.