"That which can be destroyed by the truth should be," wrote author P. C. Hodgell.
I wish there were a gentler way to articulate that wisdom, but I can't think of one. Instead I'll suggest a way to apply it so as to make the end result more graceful than shocking: Don't pour out the whole truth all at once in one big dramatic gesture.
Do it gradually and tenderly. As you do, keep in mind that when the truth has finally dismantled the thing that could not endure the truth, you may be able to use the debris as raw material to build something new that the truth will feel right at home in.