The only thing to do is to accept what your brain is throwing at you and learn from it. But what is possible, is taking actions today that are going to make your brain better able to make healthy decisions in the future.
Please, please read some of the different Mental health week articles, they are so awesome! They kind of helped my understand why I might have anxiety.
Mental illness is serious and valid and needs to be accepted and helped instead of shamed or not believed, but having a mental illness does not give you permission to treat someone else like shit. Do not use your illness as an excuse.