Re: borrowing trouble?!?!!?
I would like to reinforce some of the main points already made, while offering a slightly different perspective.
My first two children were each in daycare by 13-14 months. Late Son was no longer nursing by that age. Elder Daughter was, but I was feeling guilty about it, not knowing any better. (I came from a family that had breastfed, but that always switched to a bottle and cow's milk by age 1.) And I believe Elder Daughter had already had at least one overnight stay with Grandma by that age. (Can't remember for sure; that was nearly 20 years ago!)
Despite these factors--the bottle-feeding, the lesser attachment, and the weaning or thoughts that I "should"--I could not have left either of them at that age for a 5-7 day vacation! Not only would it have gone against my feelings, but my family--farm people with whom children come first--would have been aghast at the very idea! (Leaving baby with Grandma overnight was one thing--that was family bonding. Leaving baby for something so "frivolous" as a vacation would have been something else entirely!)
Now, with Happy Toddler (19mo), I'm a stay-at-home mom and still nursing--willingly, this time. HT still needs the comfort of the breast at night, even at this age, so leaving her overnight anywhere is out of the question. Hubby and I will sometimes leave HT with in-laws for up to 4 hours, but it isn't very often yet.
All told, mama, I'm thinking that you aren't being silly, you're having some strong "baby first" instincts. And I'm also thinking that you and your hubby have some difficult conversations ahead. Here's wishing you good luck with them! I hope you can find a compromise that lets everybody win.
Happy Toddler, 19 months, still bfeeding
Late Son, passed at age 8, bfed 5 months
Daughter the Elder, age 19 yrs, bfed for 22 months