I tried everything I could to get her back, and it didn't work.
No, you tried only what you wanted to do in a deceptive way that everyone tried to tell you wouldn't work. There are lots more more constructive ways to win someone's heart & especially when you have a bad track record with them. Again, a lot of people go through a horrible period after a break up with all sorts of crazy thoughts but acting on them is not a good idea & causes even more harm to ourselves or the ex.
Desperation is not an aprodesiac nor an attractive trait in a person.
Right now you have the opportunity to make the needed efforts to become better partnership material. That would increase your odds of having a good relationship in your life with her if she does ever come back or someone new. That includes being honest with yourself about yourself, with professional help. Many people also need to take anti-med's at least for a short time to get their thinking back on a good track & put brakes on downward spiral. It's a horrible time to get through but there are a lot of good ways to do that.
It also includes dissecting this "love" you say you feel for your ex. You know, the one that caused you to treat her so badly when she was with you. The one that writes a past about how you can't attract women as good looking as her so you want her back instead of mentioning the qualities other than appearance that made her an ideal partner. The one that still lets you think that treating her badly by tricking her is a good thing.
Please put that incredible energy & willingness to do "everything" to win her back to better things than researching how to deceive her with a fake a head injury into learning what great relationships consist of. If you do get a second chance with her, you want to really be prepared to make the relationship work & keep it that way so you won't go through this again if it can be helped.
It sounds like you didn't get to experience real love with her as much as loving how she made you look being with you because of her appearance. Obsession isn't love. Some professional help would help you sort out what your actual feelings for her & your relationship with her vs. the fears / insecurities that drove this despeserate plan of you. There is a lot that could be at work that is misleading you into thinking that all those feelings you have are a result of losing love & how special to you she really is as a person not just a decoration on your arm. Some is, but not all.
Any time a loss is suffered it makes us vulnerable to opening the wounds of our past losses, increasing fears & lots of anger in our lives again & the pain is accumulative until worked through. So while you may feel that your suffering is solely based on the strength of your feelings for her & the loss of your "perfect partner", it has a lot more mixed in there than just that. Maybe even the anger that someone else will win her heart, because you don't like to lose, period. Or as you mentioned that you aren't happy with the looks of the women who will go out with you so that's making you want to cling to your ex that much more.
Until you learn how to deal with your feelings constructively, this entire process is going to be a lot tougher on you than it has to be.