Catch-22

It seems like I'm always at odds with my friends. I am, by nature, a helper, which sometimes translates into me being nosy, or controlling, or interfering. I'm also a really smart person, which makes it hard for me to keep my opinion to myself. As a result, my friends sometimes don't like me, when my opinion about how best to help them conflicts with what they want. What is the best way to solve this problem? No idea. I'm generally all right at backing off, and honoring a person's journey. But two things are working against me in the cases in point: first, I truly care about these friends, and whether they end up happy, and the choices they are making are harmful to themselves and to me: I hurt when they screw up. The second thing is that one of them has asked for my help. I'm doing my best to be available without being bossy; it doesn't always work, and we've had our fights, but I'm doing the best I can. But the hard thing is when he is either persuaded by my other friend to give in, or he decides personally to take advantage of my trust, and "protect" me by withholding his feelings. I've tried to communicate to them that this doesn't work, but it persists. What do I do? I cannot abandon my friends, but neither can I support the destructive things they are doing. Which side of the fence must I land on?