Put stock in

Put stock in, take stock in: botar confiança em, acreditar em, confiar em

“Considering his general unreliability, I can't take stock in what he has told you.”( www.dictionary.reference.com) 

On the skids

On the skids: em declínio, prestes a entrar em crise ou problema

“ Her health is really on the skids, but she stays cheery anyway. “(www.thefreedictionary.com)

“ My newly started business is on the skids.” (www. idioms.yourdictionary.com)