I have a mental illness where whenever something like, say my girlfriend smiles at her male best friend finally texting her back after a while, rather than being okay about it I start panicking, and thinking things like "he's here to take her from me" or "is this how mine and her relationship ends..?" And "is she going to cheat on me with him, or is she already cheating on me?" I can't talk to my dad or a therapist, as my dad would just brush it off like he always does... I'm hoping if I can find out what this mental illness is I can use youtube or Google to find ways to coupe with it until I'm old enough to move out.