1) Annoyingly self-righteous 2) Informative 3) Instructive 4) Moralistic 5) Sermonizing 6) Tediously didactic 7) Tediously moralistic 1) Didactic 2) Instructive 
preachy Having, or revealing, a tendency to give moral advice in a tedious or self-righteous way.
adjective inclined to or marked by tedious moralization
tediously or pretentiously didactic.