Help?!

I need some advice please! So my bf had confessed to cheating  few weeks ago, I gave him another chance and he promised and does what he can to prove that What he did was a mistake and that he'll never do anything to hurt me again. What I can't seem to shake is the constant reminders, it still feels like he had only just told me hours ago, and the hurt hasn't seemed to fade. I want things to be better, I'm trying desperately to move one but I'm still struggling with it. Any advice, or what have you done in a similar situation ? I'm so lost .