Hi Nikita,
Thank you so much for sharing your comments with readers; what an inspiring story you have shared!
As for favorite mantras...my own usual meditation practice does not make use of mantras. But I have studied and practiced mantra meditation before. The key is to choose a word that has no meaning except within your meditation. Why? The word or words need to be divorced of external meaning, else the analytical function of the mind, coupled with memory, will activate and start making connections to your mantra. So if you use the mantra 'cinnamon roll' it has many associations so your mantra will immediately pull you away from your meditation. The mantra, therefore, needs only to have a private meaning associated only with your meditation practice. Does this make sense?
With smiles,
Jason