Oh OP, I've read the thread and have no real words of wisdom but I really feel for you. I wanted to share my experience of going away with formula, as nobody else has yet. I was also dreading it and it was fine.
I BF DD to about 7 months then slowly weaned to bottle over a month or so. Went away when she was 10 months, so a little bit older than yours, but she was still having 4 or 5 milk feeds a day/night.
We took a box of powder, and 4-5 bottles I think. We used the dishwasher and Milton fluid to sterilise BUT if you're going somewhere with a microwave I would really recommend the MAM self sterilising bottles and/or microwave steriliser bags - have been using these with DC2 and it's so easy, all you need is water.
We used the little premixed bottles for any feeds when we were out and about, but I don't know if they're available for the special formulas. If not, I'd either premix at home and keep in a cool bag with a freezer block thing, or else take a thermos of hot water, use a shot of this to sterilise the powder and then top up with cold water to make it drinkable. DD was happy to take formula at any temperature, which helped.
I'm not going to lie, formula is a bit of a hassle. But with formula you can share the hassle around the family more easily than with boobs, where any hassle that there is falls exclusively on you.
Well done, you are doing so brilliantly. I really hope that things improve.