you are barking up the wrong tree...

I have been single for about eight/nine months now, it's different yes, but I can also do what I want and what make me happy. After a messy(ish) breakup, my ex and I (mainly myself) decided to remove all contact, as it would just end up in us reuniting or arguing, which I did not want or need. I will admit there have been odd moments where we have had full conversations, but also months with no contact.
However the day after boxing day I received a message from them asking me whether or not if I had pushed into his new flame whilst out in a nightclub and asking her where he was. I had to kindly remind him that sort of play is not my style and if he remembers I am an absolute mouse when it comes to confrontation. So he said he believed me to my relief, or so I thought. On the return to school I had some of my friends, who were also friends with her ask me about the event and I was absolutely gobsmacked that she was telling everyone that I would do a thing like that! I have never spoken to the girl at all apart from when I have served her at work. I quickly put out my story to refrain from any bad press on my behalf.
THEN...
The following week, I was casually eating lunch with my friends, when she sat on the same table as me with her friends, where my friend pointed out that she had rolled her eyes at disappointment of sitting on the same table at me. The whole lunch experience was unbelievably awkward, just because I know that she hates me, for no reason whatsoever. The plot thickens. My friends and I decided to depart this icy atmosphere, only for me to be called after by the new girlfriend and her friends with barks. Yes, they were literally barking at me. I gave no response as I was unsure whether it was directly at me, but after much thought, there was no one else that it could be directed towards other than myself.
If he had cheated on her with me then fair enough, bark all you want, but all I simply did was be his first serious girlfriend in a relationship that lasted a little over a year. I am sad the relationship ended to an extent; however at that moment  due to a lot of issues I couldn't make the relationship work or feel as if I could make him truly happy. He said that I did and that we were fine and perhaps yes, in hindsight, if we had worked harder at the relationship we would still be together now. But I am happy that we did split. I have achieved so much by finding myself again. I have lost around 2 1/2 stone, I have offers from university, some issues have resolved and I have refound my friends once again.
I hope he is happy too, that is why I am glad that they are together, as if she can make him smile in ways that I didn't feel that I could anymore then thank you is all I have to say. So please do not get the wrong idea and do stop barking at me.