You can get a K1 approval with one "in person" meeting at the airport for 1 minute before you reboard and fly home. The meeting doesn't have to be substantial to pass the USCIS i-129f "in person" meeting requirements. Additionally USCIS does not require you to prove you have a real relationship with the initial i-129F application packet. This is a mistake many people make in my opinion because they get so hung up on proving their relationship is real versus reading the directions carefully and providing everything they asked for exactly and nothing more.
On personal note - You should really reconsider your path where you want to move forward with someone you have only met in real life 11 days total. I also have a relationship with a Cuban. I met her randomly on my first trip to Cuba in 2017 and I wasn't looking for love but a friendship formed from a spark I noticed. We remained online friends for 5+ years and during Covid a romance developed online. I traveled to see her again in Sept 2021 during the height of covid which at the time all flights from the Americas were canceled. I had to fly from NY to Spain, and then from Spain to Havana, and then had to be locked for 5 days in a "quarantine hotel". I then spent the next month with her. After that I traveled to see her for 1.5 weeks in Nov 2021, 2 weeks in January 2022, 2 weeks in March 2022, 1 weekend in may 2022, we both traveled to Trinidad and Tobago for two weeks in June 2022, and then I came back for a week in July 2022, and then two weeks in September 2022, and then a weekend in Oct 2022, 1.5 weeks in Nov 2022, and then two weeks in Jan 2023, and finally she arrived to the states on April 7th 2023 on i-134a. Why am I telling you all this? This is important - Even with all of this in person visit, it's a huge change going from "full time long distance romance" to "full time 24/7 in person living together". We talked often about how our relationship would change when we were finally living together full time and it did, it was as we thought it would be. In my situation the transition has been quite successful. We are still in love and we are living a good life together, however I'd be lying if I said there aren't difficult times where we need to work through relationships. A long distance foreign relationship is no different than any other relationship, the only difference is you aren't spending enough time together in person to really discover the potentially real deal breakers.
I'd highly encourage you to find some way to see your partner more. Borrow money from friends or family if that's what you need to do.... but without spending substantial time together you are really sitting yourself up for failure and heartache.