Is 88% really a “failure”? You won’t get the money from the campaign of course, but it seems to me you proved that you could separate hard-earned dollars and pounds from their owners for this. That’s worth something.
I presume the 2000 pounds was somewhat arbitrary of a target. IMO fuzzy logic rules when dealing with arbitrary targets: 88% is a win.
It sounds like you’re kind of down, but I think if you let a bit of time pass you might come to see this in a more positive light later. Who knows? maybe you can tackle the idea again soon.
Apart from your own audience, did you do anything to try to get people to go to your kickstarter? Like guest blogging? or drawing other blogger’s attention to it by asking them if they think these topics are of interest to them?