You are doing a great job for sticking with it and you are right that Feeding the baby comes first! My LO would not nurse more than a suckle or two at a time in the beginning and we fed with a cup and oral syringe. She lost weight and I blamed myself for starving her.
Someone on this forum posted to me Rule #1: Feed the baby (maybe it was you - I should check). At that point we began with bottles of EBM and formula (still attempting to nurse at every feeding) and a week later she was nursing on her own!!
You just have to go with what works for you and your LO and know you are doing a great job!! Do not blame or stress yourself out b/c is will only make it harder.
Enjoy your vacation and Best of Luck!