I agree with most of the other replies here, but also:
consider (1) seeing a therapist and (2) reading the Tao Te Ching.
If you're so stressed out about your work that you can't lead a joyful life, and you can't even give your girlfriend the attention she deserves for believing in you – this is the most important thing in the world – then this could be a personal issue and in that case I would recommend seeking a professional outside perspective to help you sort it out.
consider (1) seeing a therapist and (2) reading the Tao Te Ching.
If you're so stressed out about your work that you can't lead a joyful life, and you can't even give your girlfriend the attention she deserves for believing in you – this is the most important thing in the world – then this could be a personal issue and in that case I would recommend seeking a professional outside perspective to help you sort it out.