Is it wrong of me to really want both of them to die in pain?

I know that question sounds harsh but really, some of you don't know what happened with me and my ex.
I loved her very very much, which is why I got extremely pissed off when I found out that she smoked, we went through it once and she chose me over it.
Then some problems occurred which caused me to end with her, but then I thought "hey everyone deserves a second chance"
So we tried once again.
And everything was extremely well, I was very happy, then the smoking returned. The choosing began once again and big argument happened until she said "ok I'll quit tomorrow" that night we went to Saint Marie's Feast. I had not seen her in a while, plus it was awkward. She had met one of my other friends (Shannon) at Chans birthday party, they kept talking and were very friendly with each other. I never thought she would cheat on me which is why i didn't worry. Then we are now back to St. Mary's feast.
We reconciled and were happy, sort of, till I saw her smoking. I knew she told me the day after but really...don't do it in front of me...
I got pissed and left with Chan.
That night another argument, but I just let it go. Why? Because I loved her.
Next day, I get an IM from Shannon telling me she smoked 16 cigarettes with her sister, of course I got extremely pissed.
I couldn't take it anymore and ended it. I cried, of course.
Then about 2 weeks ago, I get told by one of my good friends, both her and Shannon made the story up, so I would get pissed and end with her so she could go out with Shannon.....
It's like. What the fuck? Ya know? I loved her so much, cared so much about her, gave her a second chance.
For them to do something like this....... I don't know, I'm sorry to be bothering you guys with this. I just have been thinking about it so much, I'm on the verge of completely exploding and just....ugh.