For most of us, our call to follow Jesus does NOT mean we have to physically leave our loved ones. But we may need to leave them behind spiritually in order to follow Jesus. I just don't want to get ahead of him spiritually. It doesn't work that way. You aren't to choose when you are to follow.
Today is the day.
Following Jesus is a NOW thing. It is immediate. No excuse you can offer is adequate to put on hold his compelling summons. Jesus needs this man ready and committed to be in a certain place at a certain time, even though Jesus hasn't announced the mission yet. But the man can't be counted on.