Thank you for this question. It's been a long time since someone asked a question on this thread that I really really needed to think about. I think I understand both sides of this issue enough to give you some okay advice.
It sounds like the main issue is that they're nagging at you all the time about your time off school. The other issues you mentioned (i.e. talking a lot, criticizing your every move) may just be who they are... and either way, I'd rather just start with the issue at hand.
I have an ENTP friend who's made some unique life decisions since I've known her, and I used to talk to her about them in a similar way to what you're describing with the two ESTJs in your life. I was doing that (and I think the two ESTJs are doing what they're doing for the same reason) because I cared about her and wanted what's best for her, because the uniqueness of her life path worried me, because it seemed random and not like it would lead directly to a good career/life, and because if I were her and in the same place, I would be terrified. However, my ENTP friend made a point of emphasizing the fact that this was what she wanted to do, and she had everything under control, and, most importantly, nothing I could say could change her mind. That completely convinced me, and since then I have not spoken a word to her about it.
I suggest that you do something similar to what my ENTP friend did, i.e. something like "I know you only want what's best for me, but this is the path that I have chosen, and my mind and my heart are set, and as much as I appreciate your advising, I have made my decision." As much as ESTJs are inclined towards bossing people around, and asking them to do things their way all the time, most of them know a pointless endeavor when they see it. (We don't like things that are pointless or inefficient, after all.) So hopefully, after something like that, they would respect your wishes.
OH yeah. Practicality party!