Don't force someone to remember you all the time. Just stay silent and let them realize how will they be without you in their life.
Don't force someone to make time for you. If they really want to, they will.
No matter how busy a person is, if they care they will always find time for you.
Stay away from people who make you feel like aren't worth their time.
Once you feel avoided by someone, never disturb them again. It hurts the worst when the person that made you feel so special yesterday, makes you feel so unwanted today.