I would see if the Zoloft works or not -- sometimes drugs that worked for us don't work again after you stop them, or don't work for a period of time after you stop. Paxil is well known for this, and you seem to be having this problem with Zoloft. I'm not sure I understand the not having sex if you have the desire for it -- I can see if had the lack of desire that often accompanies these drugs, but if you do desire it I'm not sure why having it would be a bad thing, but you know yourself better than I do. I don't see the point in adding Wellbutrin if the Zoloft isn't working -- you'll just be tapering off and switching to something else if you continue to follow the medication route of healing, so I'd wait until you know the Zoloft is working or not working. If it doesn't work, there's no reason to stay on it -- Wellbutrin isn't going to make a drug work that doesn't work and taking it to deal with sexual side effects is silly if the main drug isn't working. So if the Zoloft doesn't work within another few weeks, I'd think the course is to stop that drug and try another or try another avenue of treatment. If you take another drug and it works but you're having sexual side effects, then you can think about adding Wellbutrin for that purpose.
There's no point, in my opinion, to go on Wellbutrin to augment a drug that isn't working. You only augment drugs that are working. I'd wait and see if another couple of weeks are any different as far as the Zoloft working, as it is said to take 4-6 weeks for these drugs to take effect. If it turns out Zoloft no longer works for you, which often happens with antidepressants, especially Paxil, the course would be to stop it and try something else or another form of treatment. I also don't understand why, if you desire sex, you wouldn't want to engage in it -- maybe you won't have an orgasm, maybe you will, but the intimacy will be there. But that's a different story. If you do switch to another antidepressant that works and you still have the sexual side effects, that's the time to consider Wellbutrin augmentation, but again, there's nothing to gain in augmenting a main drug that isn't helping you.
Sorry about the two posts -- one didn't show up and now that I've written another response it has -- the web certainly can waste a lot of time!
Thanks, guys. I appreciate the responses. To clarify, I don't desire sex but I do have a husband, so... (To be fair, I've never really had a great sex drive to begin with and I know Zoloft doesn't exactly help matters). That aside, I'm just disappointed that I don't feel much better now. To be fair, there has been a slight improvement, and my doctor thinks we are going in the right direction because of that. She thinks I should be on 100 mg, but I want to give myself time to adjust to 75 mg. I was actually on the Zoloft/Wellbutrin combo for 2 months in the summer and I felt good emotionally, which is why I am considering it now.