You know how they say that when the plane is about to crash, you have to put your oxygen mask first to save yourself and then help the ones next to you?
That is how Life works too.
There will be times when you will come across people who would sweep you off your feet, take your breath away and make you laugh till your stomach hurts, but they may grow and might not serve your purpose or help you in your growth and in those hard times, instead of blaming the universe or yourself, trust it all.
Choose yourself. Choose loving and trusting your own instinct and know that not everybody is meant for you and you are not meant for everybody and that is okay.
Know that it is okay to mourn the absence and the memories they left you with.
Know that it is okay to say No politely to all the patterns of hurting yourself again and again for their presence in your life.
Know that it is okay to love them from afar without being a part of their life.