Im sorry sweetie
I know that nothing I can say can ever bring him back for you, even though I wish it could. But he wouldnt want to see you crying, he would want you to be happy.
You just have to try and remember the time you had with him.
Be thankful for the short time you knew him, the memories you have with him. No one can ever take them away.
"Friends are forever, you might lose them but you'll never forget them."