I suggest yes you and Evan need to sit down and have an honest chat about this and make sure to keep on topic. Don't let Jeff deviate and keep it on the topic of why is Jeff doing this and why is he bringing everyone in the youth into this. Wasn't Jesus's teachings, ""If your brother sins, go and show him his fault in private; if he listens to you, you have won your brother. "But if he does not listen to you, take one or two more with you, so that BY THE MOUTH OF TWO OR THREE WITNESSES EVERY FACT MAY BE CONFIRMED." (Matthew 18:15-16) Now ask Jeff how has Evan sinned against him and if he did why isn't he bringing it up to Evan and why is Jeff not doing it the way the bible tells us to do it but instead decides to gossip about it and slander and then you can go ahead and quote your sermon on gossip you had. I think I would keep it to this topic of bad mouthing behind your back because in a sense yeah the other people are just worried and looking out for you albeit may be a little extreme. Honestly if Jeff doesn't listen you should talk to the pastor about his gossiping though and bad mouthing behind your back and how it is disturbing the youth ministry. Don't even bring up being together alone because the bigger issue is your youth ministry is being brought down and poisoned by this guy. People who shouldn't even be involved are now involved and if something is fixed people are going to leave the church possibly your parents and Evan's parents and that might cause others in the congregation to leave because they are going to take sides and that's how some churches split. This could potentially be bigger than your relationship if it gets to that level of severity and you should definitely let your pastor know.