Make a plan with deadlines, so you know where you are headed. Include the commitments you have outside of school in your plan. Have a realistic vision of what you are doing so you can make good judgments on whether or not to TA that course, put your field work off until next summer, or take a quarter off from classes to focus on your family. Frequently revisit your plan to assess your progress. If you are not moving forward, change what needs to be changed so that you are.
People eventually finish.