With any illness, but especially an invisible illness it can be hard to have a productive day. Most people get up, go to work and do their daily routine until they go to bed. When you are sick everyday it can be hard to get up and do what you must do. Some people might consider it lazy to have to take breaks or sleep a little longer.
Think about it this way, if you have the flu you are usually stuck in bed for days barely able to move. Many times, people with invisible illnesses could feel like they had the flu everyday of their lives. I for one most days feel like I am burning alive from the inside out and that I was hit by a mac truck. I do what I can everyday to be as productive as I can, but some days are better than others.
There are different ways to be productive and one isn