Trying to get over cheating

How do you go about gaining trust back from your SO after they’ve cheated? Whenever he’s not around or busy doing something I get anxious because I feel like I need to know what he’s doing every second to put my mind at ease. I know that’s not healthy for either of us especially me. I’ve also never told him I feel like that, it just really makes me have like little panic attacks even though he’s not doing anything but at work and such. Or I feel like he could be lying to me about what he’s doing and Idk if I can go on with this when I can’t trust him even when he’s telling the truth.