Say good morning in a cheerful voice when you get to work. Every day.
Have a project (or more!) on You having fun - only you will be taking care of you, so see that you do.
You are not their doctor or therapist. You can be their good colleague, a few times even a friend. Like and respect and be polite. Think about the differences in the roles, I think we can be better colleagues that way.
Thankyou I like your thoughts it shows a real respect towards others that does help, everyone