Don't be afraid to talk to the person who has died. Keep a journal. Don't be surprised by fear. After a loss, you have many new behaviors you need to learn and many new situations you need to cope with. Remember, it's okay to feel depressed.
Sadness is a powerless feeling, but it's a VERY important part of the grieving process.
When individuals are depressed, it's not uncommon to have suicidal thoughts. However, it is very important you not act on those thoughts. Wear out your questions, anger, guilt, or other feelings until you can let them go. Letting go doesn't mean forgetting. Find a good listener with whom to share.