Stress will always be present in what you wanna do. If you wanna get rich through real estate investing, multifamily real estate and through business you have to deal with more stuff than most people are willing to deal with. Therefore if you wanna be in the top 1%, 5% or 10%, you have to deal yourself with problems than no else are willing to deal with. That's the difference between a successful real estate investor owning several properties and the rest.
Dealing with starts ultimately with the way you perceive situations. Being always negative and seeing challenges as problems and complaining about your tenants, that shows me that you're really not inline with your objectives and goals as a real estate investor. You have to take a step back and be extremely conscious about the way you're talking and behaving. See this as an opportunity to grow and improve yourself and show your tenants and everyone you'Re the right person for the job!