Unfortunately, you can't make a claim of hostile work environment then.
See, the Supreme Court of the United States addressed this issues a few years ago in a decision defining the scope of our employment laws
. The concept of "hostile work environment" was being taken to its logical next step, meaning that an employer was sued for generalized harassment not really based on race, religion, gender, age, disability or FMLA use. The Supreme Court rejected that concept. In their decision that clarified that our employment laws are not meant to be a civility code. They are solely meant to address workplace discrimination
based on race, religion, gender, age, disability or FMLA use.
Some states tried passing workplace dignity laws that would make generalized harassment illegal, but no state has passed such a law at this time.
So, regrettably, your facts don't fit hostile work environment unless you are able to state that you are specifically being singled out due to your disability. If this boss is mean to everyone, that's actually not illegal in either state or federal law.