Not sure what your specific circumstances are so this might be very general.
Have you looked into refinancing? that would help so that you don't need to pay too much per month. Also it would be a good idea to start a separate bank account on the side for the sole purpose of saving so that you can pay back larger chunks when you can. Try to actively throw some money there every week, if possible direct part of your pay check to it automatically so that you 'forget' you have that money and that way you wont spend it.
Check out this article, I found it to have extremely useful resources [check the calculator at the bottom of the article to estimate your savings by refinancing]