Honestly, I don't think that Eric is worse than Dylan or vice versa. Dylan needed treatment for his depression which in my opinion could be endogenous, that is, it is not something that goes away on its own. I don't think Eric has pushed Dylan. The boys found common interests, because they had similar problems. They complement each other. Eric and Dylan had suicidal thoughts. What they did is referred to as extended suicide. This is when a person wants to take the lives of others before he takes his. For example, the pilot of the plane, suffering from depression, sends it into a deadly dive.
If they never met, they still would've needed a solution to their problems.
I just want something I can never have.