I don't think his family life fully explains Chris's behaviour. Chris was very upset when he found out his father was having an affair. This helps explain his animosity with father but doesn't explain his complete separation from family. Chris was supposedly close to his sister but even the few post cards he sent her eventually stop
Further, Frankenstein reasons that, as the Monster's maker, he owes him “all the portion of happiness that it was in my power to bestow.” In this moment, however, Frankenstein finds himself caught in a moral conflict between doing what's right by his creation and potentially unleashing more havoc upon the world
