Really appreciate the people around you.
If your mind is always stuck on the past, you are never going to be able to enjoy the present or the future.
All we have in this life is a collection of memories.
Yes, there were great memories in the past with great people. But, there are equally great moments waiting in the future.
For that, you have to really appreciate and be thankful for those who are with you now.
Be great to the people you are with.