Firstly, your friend should be assesed (medically) by a neurologist,to see if there is something causing it . I personally feel that the parents breakup would not cause his seizure,,but may attribute to it as strong emotions can play a part in epilepsy . Getting overly tired consistently and alcohol is also a trigger for turns, but if your friend has gone all his life and not had any sort of seizure before there may be something that caused it , was the tumor removed successfully and completly? Was it a benign or milignant tumor? I feel your best source of answers will come from a specialist who can do the appropriate tests and scans for him/her. It may be necessary to see several doctors before finding the answers.Try and find the name of a respected professional specialist in your area rather than just the local g.P.
Good luck