Abram was unmarried, without children. He was not breaking a commitment to his family. He was distancing himself from idol worship.
In Matthew 19:29 individuals are being tempted with eternal life to leave their wives and children breaking their commitments.
"And every one that hath forsaken houses, or brethren, or sisters, or father, or mother, or wife, or children, or lands, for my name's sake, shall receive an hundredfold, and shall inherit everlasting life."
The important detail is they are being tempted with a magnificient reward for abandoning their wives and children.
Matthew 10:33-35 doesn't contradict Jesus being the Prince of Peace. Jesus was talking about how belief in the Gospel divides people and people fearing rejection from others.