Speaking about her very honest single - which includes a tearful monologue about Justin - she said: "Everybody wants to form their own opinions anyway.
"I think the biggest problem I had this year - even with [Justin] and on his side - is identity."
Part of that was going back to the Baby singer a number of times after breaking up.
"I was trying to figure out what I'm doing, and that was the first time I was constantly being kicked down for doing that.
"When I didn't know, I just wanted to say, 'This is what I want, this is where I am'.
"In my professional life things changed, in my personal life things changed, in my heart - everything."
The former child star admitted she has made some mistakes.
"Yeah, I made some decisions that weren't great, and so did he and that's why we went through all that to only make us better.
"And he has heard [the song] and he has seen the video, and it's something that I feel like girls need hear, and it's something I'm willing to share with people."
Through tears the 22-year-old says in the video: "I know his heart, and I know what he wouldn't do to hurt me, but I didn't realise feeling so confident, feeling so great about myself and then it just be completely shattered by one thing - by something so stupid.
"But then you make me feel crazy because you make me feel like it's my fault. I was in pain."
And she was not the only one, with the Wizards Of Waverly Place star saying Justin also struggled when he say the clip.
"He thought it was beautiful [but] I think it is really hard at first."
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Originally filmed a year ago, Selena sat on the music videounable to commit to opening herself up that much and also because her feelings for the Canadian star kept changing.
"The video was supposed to come out three times but through coincidence or though changes.... in my life [it didn't]."
"After this year it is the perfect way to end a year, it is the perfect way to end a chapter. It is like this is what I will say about every single person who has judged me, for every decision I have made, for every person and every heart that has been judged for that they've done."
The judging, of course, has been on her decision to go back to Justin.
Now back on again, Selena spoke of the love and pain she feels for the man she has dated for four years.
"I support him, I think I always will.
"I'm upset when he is upset, I'm happy when he's happy. I don't want anything to every happen to him, it hurts me."
While joking she will have to go on EHarmony after all this, the star did say she hopes to get married one day - whether that is to Justin, she kept to herself.
"I'm from Texas, I want a ranch. I love the idea of family I love structure, it's chaotic in my life."
With this chaos has come some hard life lessons too but Selena says she is finally at peace with herself.
"[I learned] how to love myself first. And not just in a relationship, just my everyday life.
"I give myself so much, I let people pull at me in every direction, and I want everybody to be happy."
Which took its toll, she said: "Eventually I would be in my bathroom sobbing right before I go onstage. And then I'd just put myself onstage and I'd want to be there for those people. I never took a moment to just go, go away and be myself and figure it out. I kept pushing myself .
"I think the biggest thing I learned is, it's okay. I'm going to stop when I need to stop, I'm going to feel when I need to feel, and I don't care what comes with that or what people want to say. It's normal. I'm suppose to keep going and that's all I want to do."
- Daily Mail
