from my mom: jo kaam shuroo hota hai, woh kaam khatam bhi ho jata hai
this has gotten me thru numerous situations- from peeling onions to writing exams to being in emotionally distressing situations- basically any commitments i've made
it sounds obvious but having it as a mantra to repeat in not-so-good times is priceless. and i always hear my mom saying it and it calms me down and makes me feel like yes, i can and i will get thru this.