Not all situations are going to be the same, this isn't a black and white thing. Your friend trips over - literally - I don't think anyone, whether they practice tough love or not, is going to be dumb enough to shout at them about it. If they trip up because of a series of events they could have foreseen, or put into motion themselves, or were fully aware of and ignored, then I'd still pick them up. But then I would point out, hey, you could've avoided that if you just thought a bit harder, or stopped being so wrapped up in yourself, or tried looking at stuff from a different perspective.

Being a good friend doesn't mean getting rid of asspats entirely, or never criticizing someone's bad behavior - it means finding a balance between calling people on their shit and supporting them while they figure it out.