I really think season 4 was the one for buddie canon, those two were either crossing the line, or stepping on it, or hovering just above it, but let me tell you something, the moment Eddie put Buck in his will he crossed the line and dragged Buck with him, whatever they had after that season is no longer platonic, not at all! They crossed the line of platonicity and entered a circle where they have been going around and around again between them. Let's put it this way, let's say that when they crossed the line it was totally unconscious, I take it, but let me tell you something, right now Buck knows that he crossed the line, but it's Buck! He's always afraid that people will leave, but this way of leaving is totally scary because it's completely different than when Eddie left the 118 in season 5 or even when he went to El Paso, because he physically lost it, it sounds a little weird, but let's put it this way; when eddie left 118 in season 5 buck kept going to see him, he was there for him and they talked, he only physically left work, when eddie went to el paso, he also left him physically (and yes, it hit him harder) but they kept talking through video calls and there was this small possibility that even though buck thought they weren't going to get back together, they could visit each other, now if we look at the episodes where buck denies his crush on eddie he always does so by saying that eddie is straight, because for buck he is, and his feelings imply not only losing him physically but emotionally, and that is what scares him the most, not being able to talk to eddie (just like in the lawsuit), for him it is ruining everything again because of his feelings, so buck is only thinking more ahead and trying to prevent eddie from leaving him this time forever, I hope that makes sense, English is not my first language so I apologize if something is wrong.