Here's what it seems to me you need: First, you need to break it down into smaller sections for work, perhaps only four bars at a time if you're a beginner (some pieces, I practice one bar, but that can be a pretty hellish bar). Make sure when you do these sections that the last bar of the first one is the first bar of the second, and so on, so that it's not too difficult to join them. Secondly, pretend you are a teacher. You know where the notes are, but your fingers don't, so you have to teach them. Be careful, but play as quickly as you can without missing notes. This may be very slow, or it may be just a little slower than you're used to. The smaller sections and appropriate tempo should help you concentrate better. Also, go through your score and circle the notes you routinely miss. Practice these beats alone, then in connection with the beat before and the beat after, and keep hooking on beats until you have a one or two measure unit (if the beat is next to the barline, you need a two-measure unit).
Second, you need faith and persistence. Even if you do all your practicing one day correctly, and by the end of your session, you can play every note in time, there is a high chance you won't be able to the next day. You need to be patient with yourself and go through the whole process you used the day before to get the section perfect. One day soon you will come to the piano and find that you can do it perfectly the first time. It clicks.
One last thing: you said you have to repeat to get it but then you start to fumble again. When you're repeating sections for practice, work on developing the sensitivity to stop before you begin to fumble again. That's your cue that it's time to do something else.
thinkgreenlovepiano already helped you with the bench. Good luck to you and I hope you're playing that minuet like a pro soon.