I felt the same almost till the end of my PhD work – ideas circling around, me knowing they are relevant, but not knowing how to connect them. Dealing with it yourself is only part of the issue, another challenge is to find deal with your supervisor’s perspective on it.

A bit is here (make sure you watch the video 🙂 – http://blog.mathemagenic.com/2006/07/03/phd-supervision-a-bit-of-trust-a-bit-of-imagination/