If you're unable to leave your house often

Sometimes, I find just being able to go outside for a little bit really helps to combat the cabin fever and boredom. Would you be able to go out for a quick walk around the block or up and down the road?

One thing I like to do on the weekend is go to the Barnes and Noble, have coffee, and look at magazines. You could take your book up to the fast food place and sit and read while you have a coffee or shake or lunch or whatever.

Can you go outside? To a park, even your back yard for some sun. Pick up gardening (haha -totally NOT something I could do!), reading outside, just relaxing?

I second gardening or going for a quick walk (and bonus, both of those count as exercise!) Maybe start hosting a weekly crop at your home or a book club/ bible study?

Take some photos - could be anything you want - there are loads of ideas out there.

Macro of flowers, leaves, bugs, DUST!!! LOL

Water droplets

You and your son, doing what you do

Leads to maybe journalling a little about your journey...

Kind of like scrapping but doesn't have to be, IYSWIM!

Anyway - other ideas (if you are confined to the house a lot) would include free on-line courses in, oh, I don't know, anything you want/have an interest in (there are loads out there as well); finding a really contentious political forum and just asking a lot of questions (usually only works for a day or two before you want to poke out your own eyeballs, but could be good in an emergency); painting by numbers stuff - for when you need to just be on automatic kind of; solitaire (same reasons as painting by numbers); get a hamster (I swear this sounds MAD, but they are cute, cool and don't require walking - just depends on how son might react/interact, I guess).

Cactus growing - kind of easy on the non-green-fingered! Knitting a great long something which never turns into something but you can call a scarf later is good, too!!.

Oh, I do feel for you. I was very ill a few years ago and not being able to leave the house drove me crazy!
You've had lots of good suggestions already, the only thing I would add is what about a sketchbook? There are loads of photos online to draw from, even doodling can be very therapeutic. Good luck!

There are some great suggestions already, I would just add reading, cooking or baking, maybe start a blog? Or maybe try learning a new language if you're feeling like something like that. Duolingo is free (they have a website and an app and there are a lot of different languages.)

I am a home body. I don't work and I don't go very many places. I usually only go to town when I need to... I love staying home. I don't get bored most of the time. 

I have my crafts, I have my websites that I like to go to often, I have a few games on my tablet that I like to play. My daughter and I love to color and we usually give each other challenges for color sheets we print from the internet.  I have a few day time talk shows that I record and watch (most of the time I fast forward to the interviews)  I watch a lot of stuff on netflix.  I like doing word puzzles also. I do read but haven't lately. We are getting a hot tub (ordered it now we sit and wait for delivery) so that will take some time out of my day sitting in there each evening. then there is always cleaning house, cooking dinner and keeping the dogs from sleeping all day.. 

Swap Bot
You'll find many interesting swaps. 

-Blogging? Or, is that not popular anymore?

-Online gaming-free games are great.

-F/B-especially a group that understands the challenges in your family

-Writing pen pals

-Exercise. When do you usually have the most energy? Maybe it's not possible to workout every day, but perhaps every other day?

-Do you have anyone that can help you?

How about learning a musical instrument? There are so many choices and tons of how to videos online.

The only thing I can think of that I didn't see mentioned yet is puzzles. Pinterest is always a good diversion, too.

I was in your situation when my sons were younger. I did crafty things like scrapbooking and knitting/crocheting, gardening, and reading.

I'm there too. My youngest is currently house/bed bound due to complications of a major surgery and 5 months in and out of the hospital. To go anywhere with him requires an ambulance, so we only get out to go to medical appointments.

I like having a book on tape to listen to. Netflix movies and TV series. Music on Pandora or Spotify.

I find it'skey to have a routine for me, where I get at least 30 minutes of exercise before he's up, plus a shower if all the planets align. I've scheduled quilting days for friends to come over to my house and work on group projects with me-- usually a donation or auction item. Usually it's a smallish group with maybe 3 or 4 other ladies -- so I get a little social interaction, and I have something intersting to work on.

I also try to schedule several visits for my son -- his palliative care team members, friends from school, friends from church, neighbors. We keep the visits short so he doesn't get overwhelmed, but he enjoys about 45 minutes of seeing someone other than me.

I order as many things on Amazon subscribe and save as possible so that when I do get that rare time when I can leave the house, I don't have to waste my precious free time doing mundane errands. I also have a pretty detailed menu planned in advance so that I'm not scrambling to make meals. We keep most meals quite simple and easy to make, and more importantly, easy to clean up.

I've been trying to spend at least an hour each day cleaning out, purging and organizing. I get my son in on these projects when possible by bringing his wheeled bed into the same room with me and telling him what I'm doing. We have music playing, and he at least gets a little change of scene. My son's nonverbal and has no mobility, but his cognition is high, so it sounds like our issues are not exactly the same. But I am wondering if you could come up with some activities that would engage your son and keep him interested outdoors for a change of pace. What about "painting" the sidewalk or patio with water. My boys used to love that when they were toddlers. I let them use an old paint roller and those foam brushes, and they would coat the entire surface with water. OR a sensory bin -- big rubbermaid bin filled with beans and little toys burried to discover. Musical chimes and bells to listen to? A place where he can dig a hole? Obviously, I don't know your son's functional level or interests, but finding things to keep him interested even for a little while will translate to respite for you.