Hi James!!!!
Life can be really stressful sometimes, believe me I know!

But don't worry, because even though you're having a hard time with your job at the moment, just remember that it won't be like this forever!!! You say that you need to work at it for 12 months to get references and what not, well just keep that in mind!! You know that after the 12 months are over, everything is going to be better, so why worry?!!! Talk to your girlfriend about the time situation--you know, so that she knows that her paying the bills won't be a forever thing!!!! Sometimes when we have something to look forward to, life doesn't seem that stressful!!! So look forward to the end of the 12 month period, and you'll be fine!!!!
In the meantime, if you want to feel better, just do the following breathing exercises, they do work wonders, so try them out. Here I leave them for you:
Sit, lay or find a comfortable place to be. It would be optimal if you find a nice, quiet place where you will not be disturbed.
Breath. Feel the breath enter your nose, and feel it as it leaves. Just focus your attention on your breathing for a couple of minutes. Relax. Don't think about anything just pay attention to the flow of air through your nostrils. Do this for approximately 15 minutes. You can do it at any time that you want, be at home or at work, when you're stuck in traffice, if you're on the bus...everywhere and any time...you can do it!!!
Now, if you're feeling anxious do the following:
1) Breath in to the count of 4, and hold it to a count of 7, then slowly and steadily breath out to a count of 8. You can do this for a maximum of 15 minutes.
The above stress-reducer exercises are awesome!!! They work instantly!!!!
Hope you feel better James!!! Take care and good luck.