I believe I am giving a very good impression that I am fine without her and she really doesn't like it.
There can be many reasons for this and best not to try to mind read. Chances are if you were pursuing her, or sad, or doing anything else she would also be angry with you and/or treat you poorly. It's not about you, it's about how she's feeling inside.
You need to stay the course regardless of what she says or does. You should expect tantrums, coldness, and periods of warmth followed by distance -- keep recognizing that it doesn't have anything to do with you and is not a reflection of what you're doing or not doing.
Often when we get into a bad situation we try to change what we're doing. If you're changing a long-established dynamic, the change itself is painful because it's unfamiliar. People often give up on their new course of action just because of the pain of the transition, falsely assuming it's not working, then go back to the same situation they couldn't take anymore. Stay the course and come out the other side of the tunnel and everything really will be better.
Keep doing what you're doing. You are not her insurance policy, you are not her emotional safety net. If she didn't want you to be happy by yourself she shouldn't have left. You don't owe her anything right now but to give her space and be the best person you can be.
Acc
Married 18, Together 20, Now Divorced M: 48, W: 50, D: 18, S: 16, D: 12 Bomb Dropped (EA, D): 7/13/11 Start Reconcile: 8/15/11 Bomb Dropped (EA, D): 5/1/2014 (Divorced) In a New Relationship: 3/2015