How do you handle stressful calls?

I've been in EMS for a little over a year, but full time for only a few months. Recently, I had my first suicide call. A person hung themselves in a forest. We managed to cut them down and perform CPR. We worked them for a little over an hour(the closest hospital was half an our away while running hot). We made it to the hospital, but the ER doctor declared them deceased.

Even though we knew the patient wouldn't make it, it hit me hard when the doctor called it. I haven't really been able to get it out of my head since. How have you been able to handle those hard calls?