I don't know how many paragraphs your professor needs you to develop, but if your essay consists on just 3 paragraphs (introduction, body and conclusion) your thesis is OK.
Now, if your essay needs to have, lets say 4 or 5 paragraphs (introduction, body 1, body 2, body 3, and conclusion) I'd recommend you to add two more details to your essay. For example,
Schizophrenia is a severe mental illness that deeply affects not only the patient's daily life, but also his family and friends.
paragraph 1 is to develop how schizophrenia affects the patient daily life only. Paragraph 2 is to develop how schizophrenia affects the patient's family and paragraph 3 to develop how it affects his or her family.
Don't forget to put examples, professors love when you put examples.
Good luck, and if you need help, you can ask me.
