Why can't I win more than 3 Trophies from my opponents, but they always take 25 from me?

If you have reached the point where all players are only giving you 3 points, and can potentially take a lot if you lose, this means you are already very high on the Hall of Gods for your Ascension Level. At this point the Hall of Gods is very competitive and it requires a lot of playing and a lot of patience to make it to the top.

It's important to remember that every single other player who is above you on the Hall of Gods will lose even more than you.