One thing I've seen to help with this is the idea of "recovering" a streak. For example there's an online puzzle site (puzzmo.com) that tracks how many days in

One thing I've seen to help with this is the idea of "recovering" a streak. For example there's an online puzzle site (puzzmo.com) that tracks how many days in a row you completed a puzzle. If you miss a day the streak counter resets to zero, but if you then complete it seven days in a row, the counter goes back to whatever your old longest streak was. Of course, this is completely arbitrary and silly, but it does take the sting out of losing a super-long streak. A new goal of seven consecutive days feels reasonable; a new goal of 300 consecutive days feels impossible.