Samantha, have you considered the combination of Wellbutrin and Buspar? Buspar (often prescribed for anxiety) can be used together with one of several anti-depressants to make the anti-depressant more effective, so it might make it seem like you were taking a higher dose of Wellbutrin (but without the toxicity). I have heard of a number of people who do well with the Wellbutrin/Buspar combo.

Good luck.