Many people who have been through a breakup understand the pain and turmoil that comes with it. Sometimes, it is easier on the person who has ended the relationship as opposed to the person who is the one being broken up with, but that isn't always the case. Breakups can hurt even if both people have decided that it is for the best, even if there was no major fight that led to it happening. It can be even worse if one person was unfaithful in the relationship, but in a way it's almost harder when neither person has done nothing wrong. There's nobody to blame, nothing tangible into which you can channel your anger and hurt.
If there's anything I've learned, there is no way to snap your fingers and decide that you're completely over somebody else. If the feelings are still there, let them be there and don't fight them. In many ways, it's like trying to stem the unstoppable tide of a tsunami. The process of getting over a relationship depends on a lot of things; the type of person you are, how good the relationship was and how long it lasted, how much of yourself you put into it, etc.
As each day passes you may find yourself waking up and thinking of them. Sometimes it hits you like a shockwave that it's over. Maybe throughout the day you'll see something or think of something funny and reach for your phone to tell them, before realizing they're not there for you anymore. Maybe you'll spend hours analyzing every detail of the relationship trying to figure out what went wrong, or scroll through their social media pining at what you no longer have. It may be hard to eat for a while, or sleep. Or maybe it will be all too easy to just want to do only both of those things and nothing else. It's normal, it's human, and it's nothing to be ashamed of. And if you don't allow yourself to feel the way you do, it makes the process all the more difficult.
In the meantime, there are things you can do to fill in the in-between moments. Volunteer, pick up a hobby, watch an interesting new movie, or spend time with good friends. None of these things will make you entirely forget about the other person or make you feel better right away, but it is a step in the right direction towards learning to be happy and healthy on your own after you have spent time emotionally committing to someone else.
Truthfully, the only thing that can truly help someone get over heartbreak is time. A breakup is the loss of something, and just like with any loss, your heart may not heal all at once. It will heal little by little, until eventually you'll wake up one day and they won't be the first thing you think of. Or you won't feel that pang in your chest when you look at your phone and don't see their name. One day you will accept that the person who was once such a big part of your life is not anymore, and for some, that realization can be sobering. But it doesn't mean that your life has ended by any means.