Waiting for their explanation is like waiting for a bus that stopped running. Walk home; you know the way.

Some people will never tell you why, either because they cannot say it or because they have decided not to. Waiting for that keeps the situation open and hands the ending to somebody who has already left. The closure you are waiting for is something you assemble rather than something you receive.

Write down what you do know, plainly, and accept that it may be the whole account you get. Let the unanswered part stay unanswered rather than filling it in with guesses about yourself. Then put your attention on what comes next, which is the part still available to you.