I disagree with your interpretation in the other discussion about what the Supreme Court ruling means for federal protections, but both Florida and Illinois also have state-level protections against LGBT discrimination, see https://en.wikipedia.org/wiki/LGBT_employment_discrimination....

None of this should come up during interviews, but in the tech industry in many or most places you should feel safe mentioning in passing a same-sex significant other or volunteer work with an LGBT group or something like that. Of course bigots can lurk anywhere but if this is really bothering you then, and I mean this with all respect and kindness, that might be something for you to work on personally. That you're worried about Chicago is a sign to me that you might need to recalibrate a little.

Also, questions about hobbies or favorite books or whatever you might be thinking of should be thought of as places to let yourself shine professionally. When they ask about books it might sound like they're open to hearing about your favorite bodice ripper but really it's a chance for you to talk about technical books you like or something else suitably impressive and relevant.