What are you using for an indicator that you need to change your DE? Even in the beginning of the season when opening places the heaviest load on the DE, I change it maybe three times in the first week, then once the next week and that lasts for a month or so. I change it when bumping doesn't bring the psi down as much as it should, and it climbs back up within a couple hours. For my Hayward EC65A I charge it with 4 pounds or so and normal psi is around 12-15. With the factory recommendation of 7 lbs. the pressure runs around 20-25. Bumping happens when either of those numbers rises 5 lbs. or so.

I think you could go somewhat longer between recharges.