Clinical Depression

My husband was just diagnosed with clinical depression.  He is happy to have a diagnosis that makes sense to him.  He spent most of last night looking it up on the web.  His meds were changed from Effexor and Welbutrin to Zoloft and Welbutrin.  The Dr. said this would make a huge difference in his moods and energy levels.  I'm thrilled for a chance that things may start to get better.  Is there anyone here married to somone with clinical depression?  What can I expect with the change of meds?  How did things change for you?  How long until things got better.  I guess I want to know that there is a light at the end of this tunnel.