I'm doing fine and holding it up together outside, but inside I feel like a whole part of this world is gone and everyone is just going about life. Nothing means anything to me anymore.
Most Helpful Guy
You're in the place where you're expected to be after a breakup, remember that. Loss of love requires that you go through the grieving stage. You wouldn't expect to feel okay in a week if someone close to you died so don't expect it now either. Remember that this is a process and the grief is part of the process, as is the sadness, anger, doubt, questioning and general emotional turbulence. With time you reach a level of acceptance, closure and peace. There are no shortcuts, you have to ride through the rough seas to get to the calm seas.
Don't waste time on assuming how his life is because you simply don't know. You only know how it looks and perhaps you have second hand testimony from other people. Or you may even see his social media pages and statuses and think that everything in his world is rosy and perfect. All of that can be an illusion. His life won't suddenly become perfect overnight, he'll have trials and tribulations like the rest of us. You have no idea how his new relationship, if he is in one, will pan out. If he's gone into it quickly then there is nothing to say that he will last.
Put him out of your sight, don't look at what he is doing and don't let people tell you how he is doing. It doesn't do you any good. Focus on filling the gaps in your day and your life that he has left. Keep your eyes on the other side of this dark period, know that there is an other side. This is not permanent, it's just something you have to get past.
Most Helpful Girl
You will get through it, the slump, the feeling that part of your world is gone, that is normal. For a while he was a very important and significant person in your life, and now he's suddenly not there, part of your world IS gone. But you will be okay, so many others have lived through heartbreak and survived, you will too.
You might want to distance yourself more from him. Don't see him, unfriend him on all social media, don't go to places or do things that remind you of him. You do not want reminders of him while you are trying to get over him. Recognize if there are certain things that trigger memories of him, then avoid those things or actions (and sometimes this means not seeing mutual friends of his and your's for a while). And don't compare your progress to his, everyone gets over relationships at different speeds, it doesn't mean the relationship didn't matter or he never cared.
Keep yourself busy. Spend time with friends. Make new friends. And cry if you need to. Take up a new hobby. And slowly, day by day, week by week, month by month, you'll find that you miss him less, you think of him less, and one day it won't hurt to think of him.