It can’t be denied some Breslovers have disturbing tendencies (maybe they got it from Berland?). See more here for exempla, and the money quote:
I don’t think I have a problem with Breslov, but if it’s getting distorted into idolatry, I certainly do.
I now quote from centrist Breslov.org’s FAQ page:
Is the Rebbe an intermediary between the Chassid and God?
The Second Commandment forbids us to accept any mediator between God and man. There is no sense in which the Tzaddik carries out some form of devotion which then absolves the individual Jew from fulfilling his own religious duties. On the contrary, Rebbe Nachman’s teachings call on each Jew to accept responsibility for his life and take practical steps to develop his own personal relationship with God, especially through intense prayer and hisbodidus.
At the same time, Torah literature frequently portrays the Tzaddikim interceding with God on behalf of the Jewish People, as Moses did after the sin of the Golden Calf, when he prayed to God for forgiveness (Exodus 32:11-13). Similarly when the Jews were taken into exile in Babylon the soul of Rachel came forth from her grave entreating for mercy on their behalf (Rashi, Genesis 48:7). Rebbe Nachman thus emphasized the importance of turning to the Tzaddik to intercede in times of trouble. It is like when a private person is summoned to court. Recognizing his own inexperience in matters of law and court procedure, he turns to an experienced advocate to help put his case in the best possible light.
Belief in the power of the Tzaddik is quite different from relating to him as an intermediary. Having belief in the Tzaddik means recognizing one’s own inadequacies and accepting that the Tzaddik is wiser and more saintly. Because of the Tzaddik’s closeness to God, he is able to reveal the ways of serving God to others. The book, `Crossing the Nar row Bridge,’ (Chapter #17) explains this concept in detail.
From Breslov.org, here (question #14).