A very hard lesson to learn is how to simply say "No."
It took me half a lifetime to learn this. I used to be consumed doing things I didn't want to do until I decided enough. Saying "no" freed me. I don't make an excuse for why I don't want to do something, either fact or fiction. I just say "No" and move on. It's wonderful!

You already said yes, but maybe after you see the kit, you can tell her it is not something you can or want to do, and then it send back. If she insists, or you feel uncomfortable with that tack, take your ever-loving time about it. You quoted them a time to begin with, a "kit' makes no difference. Good luck to you.

I would mention to her that the next time she comes across something like this, to please discuss it with you before making a purchase :D:D:D

Send her a "kit" of something (even if it's paint by numbers). Let her know "how much more fun it would be if we made it a swap". Hers will be ready when you receive yours in the mail. Is she good at anything? Make it comparable. Let her know you really want this, but don't have the time to do it yourself. In the end, maybe you'll both end up with something nice...

From me she would get a crossstitch kit of "The Golden Rule"; even if I had to make the darn kit up myself with instructions.

If it were me, since you said you would make it, when I finished it, I would send it along with a book from Miss Manners.

You're never too old to be given a refresher course in manners.

The most important thing for you to do is make sure you know the meaning of FRIEND. My friends wouldn't do something like this to me.

you hit the nail on the head.

I made her a quilt for a housewarming last Christmas--one I wanted to do because it made me think of her.
----------------------------------------
This sounds like it is where they got the idea that you were just quivering with eagerness to make them other quilts, so let's start with something small and work her up to large ones.

I've known folks like this, do something that you feel they would like and they will like much, much more.

Be kind, be courteous, be friendly, be firm as heck and if you don't want to, the word NO is not too easy to say but necessary with some folks.

I would tell her that it depends on the kit. I wouldn't commit myself to doing it until I saw the kit first. Once I saw it, if it looked appealing to me, I would do it and know that I was really doing it for her and not for him.

I'd send her a basic quilting book and offer to give any advise she needs to sew the project herself. If she and her husband like quilts so much she should learn to do it.

I'm in somewhat the same situation. My friend's quilt is now 2 years past the time I intended to have it ready for her. Partly because I bit off more than I could chew as a new quilter and tried something beyond my skill level and had to take it all apart and start over. Once I got going on it the second time around, I'm actually enjoying working on it! And I learned a number of valuable things while working on it. She has been very understanding as she is working and going to school and has two kids, so she knows first hand about not getting everything done in the time frame originally intended.
Hopefully your friend will be equally understanding if you don't just hop on the project super fast and finish it quickly.