How can I file a complaint against my employer?

You want to keep your job you suck it up with the nicotine. Maybe she or someone she loves was just diagnosed with cancer and you happened to be in the wrong place at the wrong time. Better yet kick your nicotine addiction and join the world of the socially acceptable. You will not win by making waves and you will be "noticed" as a problem and at the first time you do screw up your a$$ will be a giant target to get fired.