I'm somewhat confused by the type of players: I just played three games in DR (Div8) with similar outcomes (all games were with 8 scored goals).
First game - lots of fun: was down by two goals, equalized, again down, again equalized, then the opponent in the 83' scores the fourth goal and start passing between the GK and CB. I was so disappointed, since it the game was that good and when I took the ball, I scored an own goal).
Second game: down by two goals, equalize, concede, again equalized, he scored the fourth and I equalized in the stopping time. What I did not say yet is that he watched every replay, every "walk back to own half" and of course, celebrated every goal. I did none of that. Furthermore, the 4th goal of his was a "kick-off goal".
Third game: was down by three goals (I should definitely work something out with my defending in the first half), equalized, the opponent scores the fourth in 75', and the fifth in 87' (after I missed my chances). He celebrated his first three goals, then stopped (probably after he saw my behavior). Did not waste time, in every aspect, this was a positive example.
I enjoyed all three games, irrelevant to the overall score (0-1-2), but ended up with very different opinion on three opponents that I've met.
Which all leads to the question: why does not EA enables feedback from players. This is probably one of the more natural ways to correct behavior that annoys many players. Surely, if a player receives a negative rate from someone out of spite, this would be an isolated case, not affecting (much) the overall rating of that player. So basically, this would be an etiquette grade - not rating, and you could for example set in preference "not playing with those below 4 stars or smth).
Sounds like you need a lesson in the "Score first" technique. I would highly recommend acquiring an icon such as Dennis Bergkamp to help you