I didn't make it through all the posts.... but wow.
Here's my 2 cents.
I left my DS who was 100% breastfeed at 4.5 months. It was not for a life-threatening emergency or anything of that effect. One of my best friends was graduating from law school and I wanted to be there for her. Although I'd flown many places with DS before that point, this just wasn't a trip that I thought I could handle with him. It was 48 hours.
I had plenty of frozen milk and pumped religiously while I was gone. He wasn't thrilled with taking a bottle (never has been) the first few feedings, but his daddy loved him and cared for him and he did fine and was relatively happy the time I was gone. He was very happy to see his momma when I got home... and went back to nursing fine. I also brought a stash of milk home with me.
I honestly never even considered that I was not AP for taking this trip, but obviously there are plenty of mamas here who think that.
As for the breastfeeding relationship - I would *NOT* have taken this trip if the option was to give formula. But it is very possible to continue your breastfeeding relationship during a short absence. Does your DS take a bottle? How often? There's always the option of syringe or cup feeding as well.
I will be leaving my now almost 14 month old DS who is still nursing for the 2nd time in his life for 48 hours next month. I really struggled with the decision this time as I did the first time, but I feel DS's needs will be met well by DH. Actually, this time the decision was harder than the first because I feel my nursing relationship is MORE in jeopardy this time than the first since at 5 months DS was much less at risk for weaning. But anyways - sorry that is OT. And I know many moms here won't approve, but I wanted to share my experience with the OP.