I don't use it. Never, in years and years of writing. OK: in a series of long phrases where a comma would just be more confusing. But in 99% of cases I use a period. If I'm in a scrape, I'll add a conjunction to a comma. I'm not above the ellipsis ... at all. I overuse it in fact. I'll whip out the em dash -- which I also overuse and love. Why? It's so out there, so visible and dramatic, and maybe I was programmed because of James Joyce hating quotation marks. And I love the colon. Here's why: because Kurt Vonnegut used it so much, and I wanted to write like him. He wore off, but the colon remained in triumph.
But the semicolon? Come on! What is it, even? It's half-assed, tentative, blase, worthless garbage, if you ask me. Shit or get off the pot, semicolon! If you divide two independent clauses, you just can't compete with the period, I'm sorry. Sure, you show those clauses are related, but duh, who really has trouble getting that from the context? You don't supply the pause between dependent phrases, don't introduce a series, indicate time's passage, or refer back stylishly to a point just made. What the hell do you do?
And yet I fear I'm wrong about everything I just said. I fear that the semicolon is indeed a unique and valuable citizen of conjunctionland. That it is I who is at fault. That I just don't know how to use it. That it's my blind spot, my Achilles heel, my embarassing gaffe. That my novel won't have one semicolon in it, and reviewers will be all over me. Hell, I may as well admit it: I'm freaking scared of the semicolon. I mock what I fear, and I fear what I do not understand.