Unable to pump, going away for three days.

This is still a while away, but my partner and I are going away for three days (two nights) in March. My daughter will be 9 months old at that point, and is 80% breastfed currently, but takes formula on the two days a week I work since I'm unable to pump. I'm not worried about how she'll do without me or breastmilk, since my mom is amazing with her! The problem lies with me, and how my poor boobs are going to do with her not being able to empty them for me.

I can't pump, at all. I can sit there with a pump attached for a full hour, and only get a single ounce combined after a full day of work, when they feel like they're about to burst. Then my daughter will eat off them, and gulp it down effortlessly. I've tried all the tricks. Leaning forward, heat, breast compression, looking at pictures of my baby and imagining it's her suckling, dim room, relaxing music, pumping while she eats from the opposite breast, a hand pump instead of my double electric, hand expressing.. You name it, I've tried it! I just don't respond to it.

I'm not ready to wean her, as I want to make to at least a year, but I know that this trip will decrease my supply since I'm unable to pump, and I'm worried about plugged ducts, engorgement, ect. What can I do, besides just simply not going or bringing her with me?