I read your other post- tell your friend to sod off, if it's not too stressful. It really sounds like the stress of dealing with her is making you more ill, and you need to be 'selfish' and take the time to recover, otherwise it will just drag on.
Don't blame yourself for not doing any exercise- you were ill, and it wouldn't have been wise.
-------------------- "This is truly the age of bacteria: as it was in the beginning, is now and ever shall be."