What would be a good synonym?

I think the previous poster meant "in vain" but that is still a little bit cliche, unless you are reading a S. Meyers book, in which case I am out of line.

Just try to sound like you are explaining the book to your grandmother, not the one who rides a Harley and hides out in your garage when the cops come by, but the one who always volunteers at the church. Say, "basically everything she does only makes things worse," or the equivalent. Good luck. Believe it or not, writing papers is an actual skill you will use when you get out of school.

After all the character efforts s/he still came away "empty handed."

messed up. but i think you should say "her efforts were in vein" or something. make it sound more literal.