Write your MIL this:

"Dear XYZ,

I am sorry I lost it today. I do realize that your repeated attempts to implore me to get better my thinking positive and praying were well-meaning. However, they hurt me a lot, because they are vacuous. You do realize, don't you, that had all mental illness be easily "wishable away", if you excuse my coinage, then it would have long been eradicated from the face of this Earth?

I do value your support, but such vacuous advice is counter-productive. It is much better when INSERT WHAT THE MIL DOES WELL.

Again, I appreciate your desire to help me, but please refrain from telling me to think positively and pray.

Thanks. I look forward to seeing you soon UNLESS YOU LIVE IN DIFFERENT STATES".

I beg you to write it, because this problem needs to be nipped in the bug - without appropriate negative feedback from you, she would continue on and on. I will tell you a story about my MIL (who died last year). She LOVED everything miniature. Miniature gifts, miniature toys, miniature books. She would give my daughters numerous miniature plastic dolls and once gave me a miniature cookbook. The dolls were a result of poor craftsmanship and one part or another - a head, an arm... - would always break off. Miniature plush toys, miniature toy plates and cups with miniature utensils, etc.

The miniature gifts added to clutter, and since I generate clutter myself, extra clutter was really NOT welcome. But I never told her to stop sending those ridiculous gifts.

She is now dead and I am now divorced from her son (who took our daughters but that's another story) and am hard at work decluttering my apartment, and now and again I happen upon something MINIATURE! Yesterday I put the miniature cookbook (full of many recipes and housekeeping advice printed in a tiny font) into recycling because I realized that I would never read it - if I ever want to read cooking advice, I can get it online in the font size that is comfortable to my eyes.

In other words, she is dead, but I am still dealing with the harm she caused by her boundless "generosity" when it came to giving miniature crap as unwanted gifts.

Your MIL is exactly the same, except that in place of miniature dolls whose limbs and heads break when one tried to play with them she gives you the "gift" of unwanted advice. Nip it in the bud!