Have you ever seen a baby take his or her, first steps? It is a sight to watch, they hold on for dear life! They haven't figured out gravity, but they do realize that there is a need to hold on, so as not to fall. So, they start off slow, but when they think they've got it, they let go, more and more. They also learn that if they fall down, they can grab hold of something and get right back up and on the move.
I have suffered from depression, unknowingly at first, but then even after I knew, I found it hard to get back up. This is where the baby steps came in for me, first acknowledging that I hadn't figured out the source of my depression and then having the wherewithal to hold on, so as not to fall even further.
There are subtle signs of depression, such as small loses of wanting to do something or go anywhere. I say small because, everything starts out little by little, then before you know it, you are struggling to do what you have to do, like brush your teeth, bathe and go to work or school. You want to sleep or be alone a lot, and you find that you are satisfied with that, but the people who know you, know that something is not right with you.
I'm not a doctor, and I'm not saying that every time that you lose interest in something or don't feel like doing what you use to do, means that you are depressed, but it is something to take into consideration. It took me years of being depressed and even more years of finding out what was behind the depression and what steps to take to get out of it. Step by sometime, baby step, you can come out too!
Even as a believer, you can be depressed, it is real, and it is no respecter of persons. Please, get help if you need it, and if it's not you then please help someone else that you think may be suffering. Yeshua a.k.a. Jesus came to give life abundantly, He is there with you even in you're suffering, don't give up on Him.