Your FIL's behaviour is rude but easily explained - he's upset. Telling from my own experience. Over 22 years ago I married a foreigner. My late Dad was upset that I've chosen to live thousands of miles away from my parents, though he wasn't rude about it.
Though I was very much in love with my husband, there are many things I regret about leaving home. I wasn't there, when my Dad died. My Mum didn't see my firstborn until he was a year and a half old. I missed sharing all the milestones with her.
My elder son has severe autism, so I haven't been travelling with him back home for over 14 years. My Mum comes to visit us once a year, and stays with us for a month, and every time she has to leave, we don't know if we'll see each other again. It's hard on both of us, as we have a very strong bond. Yes, there is a daily phone call, and Skype, but it isn't the same.
Yes, it is ultimately your decision, but you're changing not only your own life but their lives irrevocably.
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