If your wife needs help, then get it to her. Just be sure that either you are there with her or she knows that medicine should be a last option.
Will is right in that the US tends to just throw prescriptions at everything hoping it will go away. Opting for drugs such as those will only increase the dependence on them, quite literally like an addiction and should only be used sparingly.
TLDR Get help and avoid drugs at all reasonable costs.
I mean i don't wanna give advice to anyone who is super depressed. If you're super depressed then yeah, seek help. Try seeing a pyschologist first if you can, though. They can help you talk through your problems. All a psychiatrist is gonna do is get drugs prescribed, because that is their job.
I was talking in MademanG's case though. He's only mildly depressed. He doesn't want to go anywhere near anti-depression medicine. I've been on various pills through out my life for both anxiety and depression. Anti-depression medicine is used to "fix" both problems.
I never really felt a difference. Until one day when I was visiting my normal doctor, he prescribed me two full bottles of Effexor. Didn't even see a specialist. Effexor was the first anti-depression drug where I felt a difference, within a day even. It wasn't a good difference though. I was feeling like small electric shocks in various places in my body, probably nerve related. I looked up Effexor side effects and was like
That's when I first realized how serious the side effects of anti-depression medicine is. It has helped people though. it's not like its evil. but, it's not a good thing either. It's something you want to tread carefully with. Anti-Depression drugs are serious stuff. They can completely change a person's personality. They have made some people emotionless. Also some of them, like Effexor are downright hell to stop taking if you've been taking for for an extended period of time.
Try googling "Effexor withdrawl" if you want to see some horror stories.
here is a link to get you started:
http://www.medicalnewstoday.com/opinions/11018