Hi Amy,
Depression can get worse gradually without being noticed if not treated properly. My depression episode was diagnosed as the most severe one by the psychiatrist within 2 months' time and had to be treated with anti-depressants and daily psychological counselling in the hospital. Activities suggested by my friends didn't work at all because I was simply too reluctant to move around and lost interest in everything, both indoor and outdoor activities. What made my case worse was that I didn't have any support group (although I had very supportive family and friends)and even though the computer was easily accessible, I simply didn't have the mood to look at it.
Don't misinterpret me thinking that all the suggestions above are not helpful. On the contrary, they are all worth trying but if you feel that your depression still persists, I will suggest medical consultation asap.

Karen