Struggling with what I should do.

Well,   I was very hopeful that the Benedryl would make me all better.  It didn't have any effect on my symptoms at all.  Now, I am feeling down again. I just feel so hopeless.  I struggle when I don't feel well to make myself come to work and walk on my cane or use my wheelchair.  I am exhausted and just don't even want to leave my bed.  Sadly, I don't have any leave because what little I build, I end up taking for doctor's appointments.  I have two children who also have doctor's appointments and such for this and that.  My son has an injury from football and needs to attend physical therapy and several doctor's appointments. My daughter has bladder issues and sees a urologist. She also has ADHD and needs to see her doctor for that through the year.  My ex husband is worthless and cries that he doesn't have the money to take them to the doctor.  The man makes twice as much as I do and pays me a mere $500.00 per month.  That is about 10% of his gross pay.  Really! He can't afford to take them to the doctor because he can't manage his money. His creditors call me all the time.  I give them his number and then he changes his phone number.  I just want to throw in the towel and quit.  I want to stay home and take care of my children and their needs. 
When I have a good day, I am positive and perky and in a great mood.  I feel like I can conquer the world.  When I have bad days, which are more often, I just want to crawl under a rock and hide.  I think of quitting my job and applying for disability.  Then I worry about how long that will take and can I afford to do that. My husband covers me on his medical insurance.  I can cash  out my retirement and use it to pay expenses but that is only going to last for so long.  If I quit, can I pursue unemployment until my disability comes thru?  Then again, I don't have a diagnosis as to what is causing my problems. My doc diagnosed me with right side paresthesia...is that enough?  The questions are many.  It seems like I take more time off than I am at work anymore.  I struggle to come in because I feel so horrible. I have pain in my right hand and my right leg.  That pain can make it difficult for me to function sometimes.  I try to stay busy and ignore it.  Last week I had to use my wheelchair at work.  People can be polite around my office and help me with doors, but I find that something so simple as using the restroom is a struggle because the other women I work with like to use the handicap stall.  They don't appear to have a disability, but who knows.  It is hard to have to wait for that stall when I have to use it. My disability is quite visible and I feel like they are inconsiderate when it comes to that.  I get frustrated because we are all so ignorant of what it is like to live with a disability.  I know that I am just as much to blame as anyone. Until I was really faced with it, I did not consider what the handicapped went thru.  I think a good training for any business would be to make people work for a full day with some form of disability.  Whether they have to use a wheelchair or a cane or blindfolded...it would serve everyone well. 
This has become quite the rant...LOL.  Wasn't really my intent. I just wanted to write down how frustrated I am with the decision I feel I need to make.  I try to talk it out with co-workers and am not getting much input.  They wouldn't know what to do either. 
Maybe some of my dailystrength friends would know what to consider...any advice or encouragement would be appreciated!
Thanks