I'm going through a similar thing, although my daughter was GREAT at bedtime, and has just started fighting us. We have a solid routine- bath, jammies, toothbrush, books, bed, and lights out- that has worked since about 9 months. But the past week she has been fighting and trying to stall me at the door. She tries to get me to cover her again with the blanky or something. What we've done is purchased a lamp timer and set it for 15 minutes. That way it's not me turning it off, and ending the fun, it's automatic. We do everything else the same, but when I put her in the crib, I tell her that when the light goes off, its time to lay down and go night night. She now stays up and "reads" in her crib. She still fusses a little when the light does go off. But it's not too bad.
The key is finding a routine that works for you and STICKING to it. Yes, it will be hard because she's gotten used to things one way. You might want to start earlier too, if possible. I'm not a fan of crying it out, but we did do gradual extinction. You do go in and respond, but at intervals, (5, 10, 15 minutes, whatever you're comfortable with) and try not to pick her up. Just comfort verbally, maybe a pat on the back or whatever.
Remember if you do cave and let her in your bed, you are reinforcing her behavior. She will learn that if she cries long enough, she will get what she wants.
I know it's hard. Good luck and be strong!