Good news is, she doesn't actually use vitamancy on other people. She just uses it to enhance herself. (Which is why she outstripped Grey so easily.)
Though I can't promise, Free, Mar won't be distrusting and upset with Grey. She did expect him to protect Althalus, which eased her worry, and in her mind he turned his back on her 'mate'. I thought I might warn he could be hissed at after this and possibly chewed out IC so you don't think it was anything personal. XD Me, I'm meh as Rtron explained the strategic reasoning for it though I didn't think it was IC for Grey to turn his back on an ally instead of providing cover from the enemy, seems I was wrong a bit. >_>