Get a new battery. Even one deep discharge event can kill a battery's
capacity.

Also have the dealer make sure that the charging voltage is correct.
There is a TSB out for a situation which makes the car run an abnormally
high charging voltage, which can kill batteries.

The TSB is # 05-034, Headlights Dim or DTC P1298 Is Stored in the
ECM/PCM. It happened to our 2003 Accord and the dealer replace the
fuse box to correct it. Even though our car was out of warranty Honda
covered the cost 100% because it was a known defect.