I know that feel. How many projects have I left unfinished? 🤔 What I find helpful is to absorb various media tied to the project I'm working on. Like now, I'm planning on a comic pertaining to this show called "Super 4", so I look at fanart, study various episodes, and look at the toys (that I will absolutely buy) to keep focused. I even tie in other projects to the show to keep me focused on it (building a certain character's ship, roomboxes, etc).
I don't know how helpful this'll be to you, but maybe rewatching the POTC movies or looking at other's fanart might give you some extra rekindling. What I also find helpful is eliminating distractions, like the ipad I'm currently typing on. It feels SO freeing drawing without it, even if it's only playing soft music.
Anywho, hope some of this rambling helps! Stay strong!