Crazy boyfriend???

So, I've been talking to this guy for a little while, he wanted to take me out on a date, never happened I wasn't that into at the time, well we started talking a little more & I kinda liked him. He asked me out, I took it, don't know if he's a keeper or not, YOLO right? Well... We don't know that much about each other & we've never met & he already claims that he loves me a lot & that he can't live without me. My bestfriends think he's crazy & I should ditch it, but I'm not sure. Got any advice?