When a person is enlightened, they have completely disidentified with the separate sense of self. They have a real firsthand experience that there is nothing in existence that is NOT themselves. So, unconditional love comes effortlessly because they experience the truth of oneness. However, attempting unconditional love from the average level of consciousness can only be abstract and ego-driven. If you still identify as a separate self, unconditional love is impossible. So, most attempts at unconditional love are premature and ego-driven, which is a hard bullet to bite. If unconditional love is real it comes about effortlessly. So, don't expect too much of yourself too soon. Work on expanding your consciousness and you will gradually remember your ability to really love.