Will this be better one day?

Uhm so I'm kind of grieving process of my last relationship and even though numerous people have said It will get better, i just...need to know that it actually will. That it won't feel like I'm drowning when I think of them, one day. I just need to know that it will get better. If it does, please share how cause I keep trying to keep busy or "pass the time" but idk. I just need to know that it won't hurt someday.