I was very lucky in having a partner who understood depression. The first thing would be a joint decision as to whether this was a serious depression. Easy enough. When I'm depressed I give up eating, drinking, and sleeping.She would take over all our transactions with the outside world. I wouldn't have to worry in any way.
Then she would begin the common sense treatment. Regular meals, all the right foods, a routine to the day, regular exercise etc There are any number of suggestions about that all over the Internet. The only thing that seriously interested me was food containing
the Amino Acid Tryptophan. The body uses that to make Serotonin which is certainly implicated in depression.
But we were both in the therapy trade so we could draw on its resources. She would usually start with Behavioural Activation. This was very new in those days. I won't go into it but here is a link.
http://en.wikipedia.org/wiki/Behavioral_activationGoogle will throw up loads of stuff on it.
Then came cognitive therapy. The definitive book Aaron Beck's Cognitive Therapy of Depression didn't appear until 1979, but the ideas were about much earlier. So we adopted them. Again there is a wikipedia article on it.
http://en.wikipedia.org/wiki/Cognitive_therapyThese two methods would play a big role in getting better but I should mention drugs.My psychiatrist had quite a role. He believed that if you hadn't responded to an anti-depressant inside two weeks you probably wouldn't. I didn't have to spend ages on a dose that wasn't doing anything. He also believed that recommended maximum doses were optional. He put me on doses that people wouldn't believe. But it would often work.
I also did things like drug assisted psychotherapy. LSD on the NHS. Not available legitimately these days.
Hope this is of some use to you.