Wren has been using Melissa for revenge because he knows she buried Bethany plus he got with Melissa to get close to Spencer. Why else would he be so interested in her instantly?
yeah, that’s kind of weird about Wren. When he isn’t close to Melissa, he’s close to Spencer and vice versa, he for sure wants to be close with the Hasting’s family one way or another. He has his own agenda with them, but I don’t know what could be his motive other than he worked at Radley before, met Bethany, fell for her, and then she was killed or injured by Melissa (in case she was really killed) or injured (in case of being burned by the liars when the jenna thing happened) so he would be seeking revenge. I guess if he’s seeking revenge for Bethany’s murder, he doesn’t really have a motive to torment all the liars unless they have done something we don’t know about it yet. I think that he’s helping her to seek revenge for what the liars did to her (could be being burned in the jenna thing or another motive) I don’t know, but I hope it all makes sense at the end!!! :)