Have you been feeling depressed ONLY for the past 3-8 months or so? Did something happen, or his there something going on in your life that has maybe led you to feel this way? You say you don't understand the reason, but then you mention "family matters".
There is more than one kind of depression. There is chronic or clinical depression, where a person pretty much endures depression on and off for a lifetime, often without one specific obvious truigger.
Then, there is situational depression. That would be where a life event (ie...death of a loved one, loss of job or financial status, break up of a relationship) causes feelings of depression. Usually, situational depression will improve once your life situation has improved, or once you have worked through the feelings associated with whatever loss you've had.
Could you elaborate a bit about what is going on? It would be great to have some more info, so we could advise you what your options are.
You reached out here, which is a great first step.
Please go and speak to your gp about these matters or even a professional that deals in depression.