It probably doesn’t help that we haven’t gotten much from her in flashbacks. Really just 701 and 703, so far. We especially need to see her and Henry’s relationship develop more, if we’re to believe that they’re true love and had a child together.
The fact that there’s still a lot of flashback time to fill in is what gives me some #hope that the character may improve. There’s about a decade between when she and Henry met and when the Curse happened, so there’s opportunity for development. I can fanwank that the Curse made her revert to the worst version of herself, which is why she’s becoming increasingly annoying in present day. As long as she learns and grows from her experience with the Resistance, and from being around Regina giving her pep talks from experience, Ella could grow into a stronger character in the flashbacks. They need to make this happen, and quickly, because the more we see of Jacinda, the harder it will be to win us over with Ella.