I think Josh and Jessica are gonna be an item for a looooooong time to come. They might fight and break up and be in an on again off again situation. But they are kind of stuck together because neither have any other prospects, which is the same reason they came together to begin with.
Even if Jessica never goes to Casper again, Cobes will still talk about her and call her his girlfriend, just so he can brag to everyone that he has a girlfriend. It's one more thing he can hold over the troles. "My Youtube trolls are just mad that they don't have a girlfriend that loves them like I do so they have to spend all their time hating Cobrah." He is too insecure to actually sever the relationship and go back to being single, he must know on an instinctive level that his next "dry spell" might last forever.
The only way I see him ending it anytime soon is if he somehow is able to upgrade to a different woman. And likewise if Jessica ever manages to latch onto another e-celeb she would ditch Jawshie in a heartbeat. But who knows when or if that could ever happen.