2 and 3 year old nephews? They will get over it.what about the adults will they aunties, uncles, mothers , fathers . Not being harsh but I wouldn't be worried about what a 2 and 3 year old thinks .As if they have that ability to understand you moving. Jeese some people have real problems on here. Leaving your 2 and 3 year old nephews behind isn't one.
Its your choice, and your life, move on,