Zoloft and Welbutrin can be safely combined.
As for exactly how this combo might effect you is hard to say.
It may be worth a try.
I was on Zoloft at one point, and was advised by my doctor to combine the two. So it is safe to use both. On Wellbutrin, however, you can not drink alcohol. My doctor simply told me to cut back on drinking, which I didn't do much anyway. After 2 drinks one night, I had a seizure in the bathroom at my apartment and woke up on the floor with knots, bumps, and bruises all over. Taking both may help, and is worth a try, but make sure you consume zero alcohol.