I know your deeds. See, I have placed before you an open door that no one can shut. I know that you have little strength, yet you have kept my word and have not denied my name. Revelation 3:8
When God closes one door, it is a promise that God has another door, a better door with His best behind it opening for you. God never takes something good away from you. He only takes from you what will cause you harm.
He will close the door on a relationship because He has a better one for you. He will close the door on a job because He has a better position waiting. He will close the door on that business opportunity because it is going to fail.
He asks that we trust Him. He asks that the doors He shuts, we leave shut.
We open them by not forgiving, by going back into the situation and making things work out, by settling, camping out, in the land of not enough or just enough.
Choose to forgive. Choose to move on. Never, ever, go backwards in life. Only go forward.
God cannot open up your future if you keep playing in the sandbox of your past.