You play lots of golf no? In that case suspect golfer's elbow rather than tennis elbow - similar but not the same injuries. In either case a good physio will be able to treat and also give you streteches etc to alleviate the problem.
And don't you work in IT? Get an ergonomic keyboard. They DO make a difference. Check out your work area carefully for posture, ergonomic issues - again a physio should be able to offer guidance.
If you work on a laptop machine then get an external keyboard - preferably ergonomic as above. That cramped keyboard and the angle it forces your wrists and shoulders into is not a good thing.
I use the original Microsoft Natural keyboard at home. You can't get those anymore. This is over 12 years old now and has never given any trouble (used every day).
At work I have the Microsoft Natural 4000 which is the contemporary version of the original Natural.
A couple of years ago I was having trouble with my right elbow. I got one of these and it made a big difference. Your wrists are in a far less stressed position, and that, in turn, takes stress away from forearms, elbows and shoulders.
Are you right or left handed? The mouse is also a killer of wrists and elbows. In addition to getting the 4000 keyboard I also switched the mouse to my left hand.