Madhukar: A true Guru is essential. There are two meanings of the word Guru. One is 'Guri', the Sanskrit term for concentration. By concentrating on the clarity of the Master, his formless love that is beyond your imagination, everything you believed to be until now dissolves. Namely the person, which is attached to thoughts and body. Your body continues to exist – at least for some decades – also your mental power, but this dogged identification vanishes. The second meaning of the word Guru: the one who drives out the darkness. The one who drives out the ignorance. So the Guru is not somebody who is giving you something new because you are already That. If anything, then he is driving out wrong ideas and ignorance. This to the second part of your question. To the first part: you can find out by yourself what is keeping you from being happy. Just observe your thoughts from waking up this morning until now, that is what keeps you from being happy.