Writing is a lonely job. As an author, you are the one to set your hours; you work at your own pace, and sometimes it can be difficult to muster up the courage to face a blank page or computer screen. The actual process of writing is a go-it-alone job, but it doesn't have to be solitary if you can find another writer who is willing to share space, time, and ideas. You don't both have to be writing on the same project to buddy up. Just set aside part of the week to get together and write for a stretch of time. Having another person involved may strengthen your commitment to writing and you may find it easier to get immediate feedback when you are stuck on something you are working on.
If all else fails, at least you can commiserate together.