Time and again in life you are rejected by .... (fill in the blank). Do you stay down or dust yourself, get up and stand strong? It's really not about them, it is all about you. Yes, it hurts a lot at the time, and you may never have seen it coming, but it happened so you should not stay down in the dumps mourning forever. You can have your fair share of grieving--within reason. Remember, those that have rejected you are not even giving it a second thought so it's all on you. They have moved on. You have to release yourself from that prison of defeat, glean the lessons from the experience you had with them and also move on. I always say, and others confirm this, it is really their loss for having rejected you--and your gain for having been spared from what you will never know.
Don't get me wrong, I truly understand that when you are hurting, being rational is challenging so this reasoning may not make sense or be helpful right now. But, trust me, as I have gone through many experiences in life and been rejected too by family, friends, etc., the list is endless. Whenever I was rejected, I grieved, sometimes for longer periods than I should have then I came to my senses, made a decision to stand strong and move forward.
Even God Himself was rejected by His own creation. "And the Lord said to Samuel, “Heed the voice of the people in all that they say to you; for they have not rejected you, but they have rejected Me, that I should not reign over them." (1 Samuel 8:7) In this day and age... how many times do we reject God and yet He always stands strong? Learn from Him and lean on Him. Stand strong and move forward.
So if you are feeling rejected today, or recently gone through rejection, you are not alone. HOWEVER!!!! Don't stay in the prison of rejection: being sad, disappointed, frustrated, angry, etc. because life is still moving forward and you may even be missing out other opportunities while you are looking back and staying in your past. Life has so much more to offer you. There will be other opportunities. Maybe you weren't ready for this season, person, job, experience, etc., so keep growing and developing yourself. Whatever the case... don't force anything to happen before it's time. Move on. Stand strong. Look ahead.
Random thought: On the flip side... you may have recently rejected someone, etc. If ever there is a need for a next time... do it gently and lovingly. Always think... if the shoe was on the other foot... how would you want to be treated? Always be wise in your conduct and judgement.