If you've got another offer, that is your trump card. Tell your boss you're leaving... you seem to have a lot of options, so why not leave or atleast pretend to? If your boss thinks you'll actually leave and you are valuable to the company, they'll do whatever they can to keep you. Hiring people is time consuming and expensive, and when you have a good person you'll do most anything to keep them.

Also - I don't understand what you mean by the cost of living increase over 3 years is more than 60%... did you have to move somewhere?