Just run from them. When you find more giants, if the other ones are still following you, let them interact.
Maybe they'll fight. They might know each other, and one of them is owning money to another. Maybe they have a past grievance, like called the other's mother an elf.
Maybe you get lucky and it is a group of giantesses instead. Then they'll get lucky.
RPG must not always be a dice rolling math's game. It is creativitcreativityy based as well. Many DM's will probably be angry at your suggestions, I would recommend you and your party discuss why you are really playing, if not to have fun.
Anyway, if the giants decide to band together and hunt your asses down, just keep running for your life! Remember the previous group of dragons you fled from? Well, maybe you introduce those groups to each other now. Maybe it is a group of dragonesses, and then things will get... weird.
This could be a whole theme from now on. You keep running from your enemies and leading them to other monsters. And who knows, 9 months from now you might all be fighting Mantico-holders.
Clarification (as suggested by comments)
These "maybes" are meant as suggestions to your DM. RPG is a collaborative game, what happens must not always be subject to the whims of a tyrannical DM. At best, he should be let known that you will follow under his rule if he proves himself to be a good DM.