Wow! You've got a lot on your plate. No wonder you are feeling so bad. I can really empathize with you on this. I don't know a lot of answers for you, but as I'm being told, focus on only one thing at a time. Also don't ruminate about it. Keep yourself distracted - TV, book. I know - easier said then done.
Maybe write down the things you can do and the steps you need to do to achieve that goal. Take breaks, don't push yourself too hard. Be kind to yourself -- you deserve it.

Good luck.