im very sorry you lost your job. its very scary to be laid off and have to get another job. You showed your loyalty to the company but they showed none to you. the company laid you off not the union. put the blame where it belongs. A union only makes money from a dues paying member. They dont look to lose members. If a company wants to shut down a store or move they cant stop them.
As far as unions being the reason why jobs have gone overseas, non union jobs have also gone overseas in enormous numbers. Wherever corporations can get the cheapest labor it will go. An example is the textile and furniture industry. Both were centered in the south , both were overwhelmingly non union , but the jobs were still shipped to mexico, malaysia and china. There is no loyalty of corportations to their employees at all unless you are a CEO with a golden parachute.

I hope you get another better job as quickly as possible.