1. Do not expect any messages from him/her.
2. Be busy.  Make yourself busy. 
3. Do not ask for someone's time.  He/she might be spending it with others. 
4. No one is busy for someone they love. You are busy too,  right?  But you can still chat him/her. 
5. Do not forget him/her BUT you have to accept that happens. He's not for you. 
6. Do not stay in the past. Accept that is was all in the past. Remember rule 5-- accept. 
7. Try to move on.  He/she had already moved on.  You have to move on too-without him. Remember, it is hard to move on especially when you didn't even make a move.
8. If it is meant to be,  it will happen.  In your case, you are meant to learn.
9. Your best will never be enough for someone who does not love. There's nothing wrong with you. If someone loves you, your 'good' will be enough. You did your best.
10. Change routine.  It is only YOU this time.  Don't chat him/her. You are not friends to begin with.