Hey Luna,
Sorry to hear you're having such a rough go of things. Everyone has these ups-and-downs, but it's certainly frustrating when you feel like crap and feel like you're missing out on life. I've had many such occasions, as have most others on this board. What I do when I'm feeling like that: invite a good friend over and watch something mindless like Indiana Jones movies, drink Gatorade, make a fire in the fireplace, curl up with a good book, listen to some new music, whatever it takes to make myself feel comfortable emotionally if I can't feel comfortable physically.
Do you have a trusted friend who could spend time with you at your place instead of going out? Do you have many indoor hobbies, like crocheting or knitting or reading or drawing, that would be relaxing for you when you're not feeling well?
You'll get through this rough patch, don't worry. Vent all you like, that's what we're here for.