Re: dont want her back but Anxiety strikes?
Thinking back, if I'm honest this has only happened when I wasn't properly over someone who split with me, and it always goes away completely when I start seeing someone new who takes my interest in the same way. I bump into girls from time to time whose very presence has in the past made my heart leap into my throat, but now when I see them I'm like 'what was the big deal?'. It doesn't necessarily mean you miss them or want them back, it's more like you feel cheated because you gave them the power to make you feel like that.
What I worked hard to do, and I'm still working hard on (with mixed results, given my other post that I'm writing), is trying to get away from defining myself by who's on my arm, putting more value in me and not in girls/relationships. Achieve that and you'll be a champion of life.
A born again hooligan only to be King again.