Hively of course is correct -- such discrimination should be unlawful. Title VII, however, is limited to discrimination based on race, color, national origin, sex or religion. Predictably the federal Seventh Circuit Court of Appeals decided that Hively's claim went "beyond the scope" of the statute. If Title VII is to apply to the LGBT community only Congress or the Supreme Court can make it happen.
The case is Hively v. Ivy Tech Community College, No. 15-1720 (7th Cir. 2016).