Although the cause of death isn't mentioned, the Daily Mail article on it points towards LifeLine, a crisis charity to support people who are struggling with mental health, suicide etc. I guess the suggestion therefore is obvious.
Mental health issues are of course tragic and many people, many young men need support. I always think that for a sportsman, particularly in an individual sport like tennis, the support available must be so difficult to find, does the ATP/WTA/ITF provide anything for people / players etc who have injuries, have shortened careers, maybe struggling with constant travelling, financial issues etc?
Also must be very difficult to be so succesful at something at a young age, look to have a really bright future ahead of you and then to have to retire through injuries at such a young age (24?).