I can understand the distress you are through. Not able to sleep, persistent worrying or past thoughts, not feeling like enjoying, negative thoughts, low energy levels, etc these all are cardinal feature of depression. It is however important to know that depression is like any other medical problem, like Hypertension, diabetes, infection which can happen to anyone. Stress is known to be a major factor in case of depression. In your case, may be the loss of job and loved one is one. The fact is that it is normal to be in grief and it will pass away, it does take time. In some the grief period can be prolonged. You will be all okay. Things will change. I would suggest you to consider taking a treatment for this.

Loss of interest, decreased concentration and attention, feeling low and disturbed sleep or appetite are some of the signs of depression. Consult a psychiatrist who will assess you in detail. If you are feeling suicidal or hopeless, seek professional help immediately.