how to get over a former friemd

okay so ill try my best to keep this as simple as possible, its been nearly two years and I'm still angry with my former best friend.

Its like a break up with your partner or something.. we were best friends from high school and was always compared to as sisters.
We got on great, occasionally we'd both get on each others nerves and need space, all normal I assumed.
Anyways, roughly 2 years ago she just stopped talking to me. there was this petty thing where one of our mates had a 30th, a group of all our friends put in to get her a gift. nobody included this girl, it came out on the night that we had all put in for a gift and some how fell on my shoulders that I was the person responsible for not including her. Even though the other people have all said we are all to blame, not just me. I apologized for not including her and sincerely meant it.

After this, some months had passed, Id seen her a couple of times to which she clearly, and embarrassedly ignored me. So I thought fine, left it longer.
A group of our best mates all went out for dinner one night and she was happy to see me and chatty, so me being open and honest, hit her up, asking why she hasn't spoken to me and why she is angry - in a nice way, I was happy to see her and happy she was happy to see me too.
To which she replied, "I don't think we are meant to be as good as friends as what we are"
Umm shocked, I replied "well sure, we do get under each others skin, I get that.."
and she replied again with "we don't even see each that often though"
Then another friend interrupted us thinking it was getting awkward.
I was so hurt, how hard was it to simply come and tell me this, or send me a text/letter, we'd been best friends for 10 years at that point.
there was some more conversation after that and pretty much to some it up she doesn't want to be friends.

After some soul searching I decided she was right, I really don't like the person she is and agree we aren't meant to be friends. She holds me to such a high standard that anything I do pisses her off (she has admitted this to another friend too, that if someone else where to do something it'd be fine but if I did, she'd be annoyed)
I've also stopped being her friend in the past, due to her actions. Its such a long story but she borrowed my car (had 2) for couple of months, while I paid insurance and repayments on it. only to return it with a massive dent that she wasn't going to tell me about until I pointed it out.
She also hooked up with one of our best friends partners, they have a kid together and everything. She never told our friend, I never did either, I couldn't break up that home because of someone elses stupid actions. I regret that so much, to this day I feel she should know but could never tell her.

She has done other things too and I totally agree, I don't want this person in my life anymore. So I have blocked and deleted her number but of course because we have the same best friends so we still run into each other.
She also dated my partners friend so she knows people in that cirlcle too.. ANNNDDD she is moving a suburb over from me too, so its hard to get away.

I seen her on the weekend, she walks up and gives me a hug and says hello, I'm think WTF you don't want to be friends, why you hugging me?? I'm fine with formals but no need to act like we best mates.

I don't know, how do I let this anger go? I'm a good person and from what shes said to other people about me seems Ive made the right choice to let this friendship go. But why am I so irriated, upset still?? I feel like Ive been nothing but a good person, a good friend, I gave her a second chance even when I didn't want to and now I look like the bitch that doesn't want to speak to her.

I have a lot of good people in my life, friends and family and am so thankful for them all and have some really good friends to lean on and who are there for me. so there is no void that needs to be filled or anything.
How do I let this go, I don't want to be a pissed off person everytime I run into her, I'm thankful we aren't friends anymore.

Any advice would be greatly appreciated xxx
Ps sorry if this sounds like high school drama, I admit I'm a lot older and steer clear well away from all drama these days!