Be the last thing she thinks of before going to bed. If you want the girl to remember you, you must be the last thing she thinks about before closing her eyes and drifting off. This will subconsciously make her think about you more and miss you even more. The more she misses you, the more she will want to get back together with you. So, use this to your advantage by leaving her heart broken and begging for more. She will always wonder what would have happened if she left you earlier. So, go out there and find another girl that can give you all the attention you need from another woman. Then, when your old girlfriend decides to move on with her life, you will both know that it is over forever. This method works because girls need time to grieve their lost love. She will forget about you soon enough but not until after she has missed you every day for a week. At this point, she will realize that you are not coming back and move on with her life.