How can I stop thinking about him/her? Why my heart hurts so much?

There's nothing wrong with thinking about someone this shows that you really care about that person and that is what makes you human. Caring about others is what makes us a good human and if you think about them want what is best for them that makes you a good person.

I believe it's normal to experience what you are going through, you feel this way because the love you had and shared with your partner is real, try to focus on something positive and try to keep busy and not think about them so much and in time everything will be ok and time will heal the pain

Think about how much you love yourself and put yourself first. Accept that you are growing stronger from the pain and learning to cope with the pain. That you will become stronger and will no longer allow yourself to be hurt. Now you are becoming stronger and wiser and learning how to accept these feelings and turn them into positive thoughts.

Your heart hurts because you're scared about them breaking up with you. If its your first relationship in a while, you'll be used to it when you freak out over things. If its a loved one that you care about so much and they get into a freak accident, you might have a panic attack and will lose sleep by staying up all night, thinking about them, or staying all day in one place waiting from them to come through the door.

time will heal, for the moment it feels hard to stop thinking but it can't last forever, nothing lasts forever and so is pain. it hurts because it is about pain because it is sad, a breakup can't be a happy thing so it is normal to feel hurt, don't run away from pain, the more you learn to accept it the faster it will go away. Sorry you had to experience that, Be strong ;)

It not easy to get over a break up. I have been through two divorces myself. What helped me was to find out what I wanted to do with my life, a direction so to speak. Once I found something that I was interested in I filled me time with that. By doing something I really liked it filled my time and mind with other things. I didn't have time to think about him.

Feelings do not fade away quickly, it seems like you had very deep feelings for him/her, it will take time, but you will get there

I think that in time, pain lessens but in order to get to the other side of it you have to go through it. Unfortunately, there is no easy way around grief. We just have to feel it. Eventually, the clouds will lift and you will find yourself smiling again and ready to go on without him. We are all brought together for lessons that we must learn to grow and sometimes those lessons hurt. Time will heal.

Oftentimes friends and family members will say just let him/her go but the mind and heart has difficulty doing this. So what to do? Acknowledge the pain, and recognize that it will take time to heal. In the meantime, do things you love to do, try something new like joining a running club, be creative at least once a day and it could be as simple as doodling, and finally be kind to yourself and manage negative self-talk.

I can feel you. It is natural to feel so. When you love someone and due to some reasons you get separated. You actually feel the pain and you think about all Ifs & Buts. But, you need to accept the fact that things are over and you need to move on in your life. It may take time but with the time, things will be alright. Till the time try to keep your mind distracted through various ways.