Hello there. I wanted to post to give you some encouragement and tell you it can be done. It may not be how you envision it right now, but it can be done, successfully.
I am a single mom to two kids, and I only homeschool one. My daughter loves public school, and she just started middle school (6th grade). My son asked to be homeschooled in 3rd grade, but I was not ready to do it right then. I spent that year researching and preparing, and thinking. By 4th grade, he was absolutely miserable once school started so I pulled him and we've been home ever since (he's starting 5th grade now). The first year was quite difficult, just re-adjusting and "deschooling" as they say. Also, I am disabled right now and I don't think I'll ever be able to work again. I had cancer 5 years ago, and I have so many illnesses and immune system problems and pain, that I am unable to do much of anything. My health is horrible and so things are tough.
Since my kids are different ages, I have no idea how to arrange high school level stuff. I do know they have it around though. I am positive someone here knows of high school kids who have used different programs. There are so many choices out there it is sometimes overwhelming. I do know my cousin was homeschooled after 5th grade, and he is in his sophomore year of college right now. Was accepted to two Ivy League colleges and chose to stay close to home at a university here. I know he used different curriculum choices and also took college courses as well. So it can be done, but unfortunately I don't know all the answers for high school level kids.
As far as wanting your quiet time, etc, I can understand you there. i am with my son 24/7. He is very much not a social person and loves his time alone. He sometimes goes to play with a boy he knew from public school, and he will play with some kids when we go out to parks, etc, but he is overwhelmed when with other kids for a long period of time. Since he's 10 now, I often get my time to myself by carving out bits and pieces here and there. I find making routines and sticking to them helps tremendously. Knowing I have an hour at night while my kids are playing and such inside the house allows me some "me time" and definitely helps. It is hard because some days I am just unable to do hardly anything. I am starting another round of chemo and I have been sick a LOT lately. I am struggling this year to keep it together and plan out lessons. A "boxed" curriculum didn't work for us last year, so this year I picked different things from different areas. I spent quite a bit of time trying to figure out how to plan out lessons now. I don't think I'd be able to do so if I was working. I am always reading blogs and how others do things to get ideas. I also live in a small space and we do our work mostly in the dining room. I put up a bookshelf and our school stuff goes on there. I bought a crate to keep his daily/weekly books in, so he can pull out his Saxon math book and start by himself. We do science together and sometimes we do other things together, too. The rest he can do mostly by himself, though I try to stick around him so I can make sure he's doing okay. He prefers me to be nearby anyway.
I know I probably just rambled on and didn't help much, and I apologize for that. My memory is not what it used to be. I just really wanted to support you and say, if your kids want to get out, to just do it. Take them out and homeschool. If you have to do a "boxed" curriculum this year, do it and figure out what to do better for next year. Sometimes it takes time for them to adjust to being homeschooled. My son did, and still sometimes wants to organize his day how his teachers did it. I wish I had more answers about curriculum choices for your kids, but I don't. Do you truly want to homeschool, and pick your own curriculum, or have you thought about programs like k-12 and such, where it's actually public school at home? Those programs give you everything you need as far as curriculum and books, and they dictate the assignments. There are some who like that and some who don't. Just putting that out there as an option.
Sorry for rambling on here. If you ever have any questions I can help you with, please ask. I am not sure if this shows up in the general discussion thread, but if not, you may want to post this question there. There are some very knowledgable and helpful members here who know a lot more than I do and could probably help you. I just wanted to really give you some moral support and say "Do it!". Good luck on your journey and your decisions.