My company failed to meet payroll. I am an at-will employee, paid monthly. Is this considered a breach of employment? Should I consider myself terminated and not bother appearing for work?
Failure to pay wages is a breach of the employment contract and is unlawful under state and federal law. For purposes of filing an unemployment insurance claim, you may consider yourself "terminated." Of course you have a right to leave that job and look for other work, but you had the right to leave your job because of your "at-will" status even before your employer's failure to pay wages. As far as getting paid is concerned, you should immediately file a complaint with your state department of labor or employment.
By the way, you should also check with your state department of labor on whether it's legal to receive a paycheck just once per month; some types of employees msut be paid twice per month.