I understand your concern. Your cousin seems to be suffering from significant ocd symptoms. However more clarity is needed regarding his problem to decide on severity of the condition. Don't worry it is not his fault, it is the hormonal fluctuations in brain which is taking a toll on his mental health. It is easily manageable with appropriate treatment so that dysfunction due to the same can be reduced and his quality of life will improve. Some therapy sessions along with medical help might be useful for him. I would also be more than happy to help you with that if you are looking for online assistance. Discussions will be held confidential. You can directly consult with me through Practo as needed. Online chat consultation is available.