DMT changes everything around you at times, it is an extremely strong psychedelic and not to be toyed with. First timers to DMT in my opinion should have a spotter, if its their first time taking psychedelics altogether i would try to convince them to try something else first, or two spotters.
She could have had a bad trip and killed herself, maybe she was murdered? I know its your friend here and it might not sound nice to hear that, im sorry for your loss and give my condolences to you, friends and family.
Also, did she have any mental illnesses, like schizophrenia or manic depression? maybe passed on through the family line? also was she on any other medication?
http://www.erowid.org/chemicals/dmt/dmt.shtml for more info on DMT