Later: I watched episode 15, "On My Way," which ends in a cliffhanger. New episodes start April 10th.
As I've commented, episode 14, "Heart," goes really well together with "On My Way." "Heart" provides the lead-up. I thought the attempted suicide storyline in "On My Way" was very well done. I wish Kurt had been shown talking to someone besides Dave who told him not to feel guilty about not returning Dave's calls. Someone like Burt, or Blaine. It would have been nice to hear that from Mercedes, but Mercedes hasn't been terribly sympathetic lately on some issues, with her asking the God Squad how they felt about singing to gay people. Like Kurt isn't one of her best friends.
Mercedes did provide one vital bit of information, saying that Karofsky had been seen and heard talking to Kurt on Valentine's Day, and that's what outed Dave. Just being seen with Kurt will do it. That's what Kurt deals with, and what all the young men around him deal with -- if they're seen with him, the assumption might be that they're gay too. Puck actually turned out to be better at handling that pressure than Finn was. Puck says he's a stud, so he can get away with anything. Blaine doesn't want to pass as straight. Mike was self-confident enough to be friendly with Kurt pretty much right away, and so was Artie, really. Kurt probably had a lot of assumptions about Artie.