There's no need to commit yourself to a woman if your only goal is pleasure or sex, not really love. At least you won't mess up a woman's life that way.
Well, he could actually have a family. Even if he can't bring them with him. He could just wait for them to die of old age before killing himself to go to another world. That way, he won't have much regrets... However, he only thinks that such things are pointless. Why bother? Overall, the only thing that he needs to focus on was to improve his damn strength and obtain new powers! After all, only those things are what he could really bring to the journey to the other worlds!