1. Grief is the price you pay for loving someone.
When you lose someone that you love the only natural thing to do is grieve. You wouldn't feel that pain if you didn't care about about them. They're gone from your life forever and you may not understand why they had to go. You may not know how to cope with them not being there. All that is okay. You're allowed to be confused and sad and you can take as much time as you want to grieve the loss of your loved one.
2. Everybody grieves differently.
No two people are alike. Each person has different reasons for acting certain ways. However you deal with your emotions while you grieve is perfectly acceptable. It's okay to not cry just like it's okay to cry. It's okay to want to talk to someone just like it's okay to keep to yourself. The pain you're dealing with is your pain, never apologize for the way you feel.
3. You are going to change.
People will talk about things "going back to normal" eventually but they won't. Nothing will ever be the way you remember and you might not be either. But honestly, how could it be? Losing someone has an emotional impact on you as well as the people around you. You're going to learn something about yourself whether that be just how strong you are or where your breaking points are. Your life is now different and you're going to find a new "normal."
4. The hole in your heart stays there forever.
Your world is consumed in grief for a while after the loss of a love one and you feel that hole in your heart when you think about it. It's that sharp pain that makes tears come to your eyes and the butterflies in your stomach do a few flips. That pain is going to last forever. Over time though it becomes dull and you learn to deal with it. You've come to terms with the fact that the person you love is now gone but sometimes when you don't expect it, you'll feel that hole in your heart hurting like it's the first time. Time doesn't heal all wounds.
5. There will come a time when you need them and they're not there.
Everyone has people in their life they confide in with certain issues or talk about with certain things. One day you're going to have something to say to the person you lost and they won't be there. It could be something as simple as talking about the baseball game or as major as a new job or family problems. Whatever it is, their absence will cause that sharp pain in your chest and the dizzy feeling to return. It's going to be the hardest the first time because you've never not had them there when you needed them. You're going to feel grief on a whole new level because you need them the most yet you don't have them and it's going to hurt more than anything.
6. Nothing will fill the void.
An emotion that nobody wants to feel or experience is grief. Many people will avoid it or try to block it out and that only creates more grief because eventually reality will take over. It doesn't matter how many people you surround yourself with, how much you go out, how much stuff you busy yourself with, how much you drink or smoke, or whatever self-loathing acts you choose to do, that pain is still going to be there and it will be waiting. Temporary "happiness" isn't going to make you actually happy and it won't erase your pain. One day you will have to confront your demons and it'll just be harder if you've refused to accept it and filled that void in your life with something that in the end only hurts you more.