He gathers himself together, though he's a fearful man now, and he's going to be accompanied by insecurity all his life. Yet he's going to fight it, he is determined to prove that God is wrong, and that he is right and he can succeed.
Whom did Cain marry? Only a few individuals have been named so far in the record, but Moses’ purpose has not been to give us a complete record of human history, but to focus on the main events relevant to God’s dealings with mankind. The existence of other human beings is hinted at even in this verse, where a city is spoken of. Scripture is clear that the entire human race is descended from one man, Adam, and therefore there was no other possibility than for Adam’s children to take wives from their near relatives, and so the most likely explanation is that Cain married his sister. Adam was created with great genetic richness and diversity, containing in himself all the different variations of human form that would come from him. In the early generations of mankind, there was not the same danger that in-breeding now produces. Later, under the law of Moses, there were limits placed on who could be married (Leviticus 18), but these are not in place at the time of Cain.