The fact that your mother and sister used to love him and now want you to move home says a lot to me. Now that you moved away with him, how is he different from how he was at home?

What flaws do they see in him?

You said that he stays angry for long periods of time. How long?

You can expect that he is on his "best behavior" with you now, before you are married. If he does nothing to change, you can expect him to get worse if you decide to marry him.