Oh it must be so hard. There are positives-you do have some warning, so you do have some time, time to give your baby the very best start in life, which is a lifetime gift, and time to wean somewhat gradually if you need to. And after all your hard work you are finally getting the opportunity to greatly improve your family’s financial future. While of course there are no guarantees and it takes a lot of effort, it IS possible in to re-lactate and bring a baby back to the breast, so the possibility of being able to nurse your baby again when you return IS there. It's a horrible, hard choice and of course being separated for so long is something no one would wish for any mother and baby. These impossibly hard choices are the worst part of parenthood I think!
ps just saw mommal's posts-she makes good points!