To the best of my knowledge, "Friends of Mejugorje" is not a cult and is the apostolate of Bozica Bartulica. Bozica and her husband Nick are Croatians now living in the United States who have close ties to the village of Medjugorje where Our Lady has allegedly been appearing to six visionaries since June of 1981.
Nick Bartulica is a psychiatrist and was one of the first doctors to examine the seers from a medical point of view. Their organization now leads pilgrimages to the site, which is currently under investigation by the Vatican. A disclaimer on the group's website clearly states their willingness to submit to Church authority should it ever hand down a decision about the happenings at Medjugorje.
I don't see any of the typical signs of a cult in this group, such as a leader who demands absolute allegiance from his/her followers, who uses fear or other intimidation tactics to maintain control over members, etc. I suspect that whatever website you visited that listed this group as a "cult" also thinks the Catholic Church is a cult - which is a very common allegation in some quarters of the vast Internet universe.
Either that, or this organization is being mistaken for the cult known as Caritas of Birmingham, whose founder, Terry Colafrancesco, whose members also go by the name "The Friends of Medjugorje." This site contains a great deal of information about Caritas and the very serious allegations that have been made against it.
For further reading, click here for a blog that lists some of the most common signs of a cult.
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