Depending on where you live there may be mental health advocates at a state or private level -- they could probably provide some guidance for you. Consumer based mental health support groups might also be able to provide some assistance. There may also be free legal services you can make use of. Don't overlook your students association.

Also, carefully review any documentation from the school so you're perfectly clear on what legal rights they were using to remove you from the semester. In addition, if there are state/provincial laws that govern the school's actions, it will likely be to your benefit to know what those are as well.