There is a reason why I am the moderator this part of the website
In my opinion it is easy to make friends if you are willing to make the effort to get out and meet people. Unlike many other countries the ex-pat population is relatively young and I know lots in their 20's, 30's and some very young 40's and 50's!
There are loads of pubs, bars, clubs, restaurants etc. Lots of gyms & cinemas and far too many shops! Have a look at Time Out Dubai online.