J.
Most important is to not add to your depression by being angry with yourself for being depressed. It is perfectly normal to be depressed, especially after having a baby. It does not mean you are a bad person or anything like that.
I have battled depression on and off for years. I tried some the drugs available and just did not like the way the made me feel. I have found a combination of diet, exercise, mediation and prayer to be most helpful.
Get rid of refined sugars and flours. Limit wheat - even whole wheat (Ezikiel bread is ok). Eat small portions of lean protein. Eat lots of fruits and vegetables in a variety of colors. Make sure you eat three meals and a few healthy snacks (like nuts and fruit, etc.). Don't eat too much at dinner.
Go for a walk every day - ieally outside. Go to a yoga class. I have found yoga to be the best for alleviating depression and PMS. If you can't get to a yoga class, use a yoga video (you can probably rent some from the library). You may be able to find a Mommy and Me yoga class, though I don't know if that would be as beneficial.
Learn to meditate (or at least to breath deeply and fully). A great book for meditation is called "Minding the Body, Mending the Mind." You can also meditate on God's word and His promises to us.
Read the bible every day and talk to God about your problems and feelings. Be perfectly honest with God and keep an open mind.
Talk to a counselor or pastor. Reach out for help. Having a baby can make us feel very isolated, which adds to depression. Seek help or at least seek friends and conversation.
As for your boyfriend, make sure he understands what you are going through. Maybe you can write him a letter explaining all this. Encourage him to do a little research about post-partum depression so he has a little better understanding of what is going on.
Good luck! Remember you are not alone.
God Bless!