I am so sorry to hear what your going thru. My partner also left me whithin a year of my becoming ill. It's not easy on any level. As far as spousal support goes, documentation of disability from your doctor may help. Depends on the length of marriage and what state your in. Anyway, disability may affect getting some amount of spousal support for a while to ease the transition.
You need to evaluate if it is worth trying for by looking at your situation. Sometimes these lawyer things cost much more than you have to gain. Is there a way to appeal to the humanitarian side of this person ? Would he(or she) agree you are sick and disabled ? If so, it is not a stretch to point out whatever is the usual legal take on this in your state, and possibly get voluntary out of court agreement.
I just spent $10,000 dollars in lawyer fees last year because my exhusband did not want to have child support raised (it had been many years since an adjustment). He argued that I was not ill, had me go see a doctor of his choosing, etc... what a mess. Very hard on my and delayed recovery efforts on my part. So, do think about what evidence you have to back your stance and what the feelings are of your ex when choosing your path and comprimises.
Also, COBRA, continuation of benifits something or another act, means that you can pay to keep the same health insurance from your exspouses company for a few years after the divorce. However, this is often very expensive. But, lyme treatment is so expensive it may be worth it. You need to find out how much it will cost by calling his(or her) company.
Again, I am sorry you are going thru this emotionally trying time. Please look to whatever family, church, community support that can help you, and get it over with ASAP so you can heal.