मैले माया गर्न जानिन होला = may be i didn't know how to love you.( It's very hard to translate excat, ecurate in english) or, the way i loved you, it wasn't the way you were expecting.
गर्न = to do.
गर्नु = have to do. (both have almost same meaning.)
मैले = i
माया गर्न = to love
जानिन = not to know
होला = may be( he was not sure he is questing to himself) past form = may be i was lacking to love her or maybe i dind't know how to love.