Hello there,
I guess things happening in your personal life can have a great impact on the effectiveness of your medication.
Wellbutrin is a strong norepinephrine and weak dopamine reuptake inhibitor. Maybe you should try something like an SSRI ( Lexapro is a good choice ) or a SNRI ( Cymbalta is a really good one but quite expansive, Effexor can be good too ).
Another thing you should try is healthy diet and physical activity as it's a natural way to beat depression. The chemical imbalances in your brain which is probably a low serotonin level ( that's why it would be good to include a selective serotonin reuptake inhibitor in your med choice ( SSRI or SNRI ), well that imbalance can also be caused by malnutrition ( a good example is that a deficiency in vitamin B6 ( pyridoxine ) may lead to anemia, depression, dermatitis, high blood pressure (hypertension), water retention, and elevated levels of homocysteine. )
With today's processed food it's early impossible to have all the nutriments ( vitamins, minerals, proteins, fatty acids like omega-3 ). Exercise is a natural anti-depressant too. It balances your hormones, you produces large amount of essential hormones like epinephrine, growth hormone, estrogen, thyroxine, glucagon but the most important hormone in physical activity is the endorphins. Endorphins is an endogenous opioid from the pituitary gland that blocks pain, decreases appetite, creates a feeling of euphoria, and reduces tension and anxiety. For you that means a happy mood.
Please consider that I'm not a doctor nor a nutritionist and therefore you should consult your doctor before considering everything i said above. They should be seen as suggestions only and medication is something that need to be talked with a doctor and physical exercise too if you have any condition that might play against you.
For more information read my post concerning the importance of nutrition and physical activity and the underlying problems of many illnesses:
http://www.medhelp.org/posts/Depression/Knowledge-for-Depressive-People/show/1127539
Best regards,
M4