Online cheating but not in person

Looking for advice.

Found out my partner has been cheating on me online for over a year. Sexting, pictures, videos to a few women off and on. And deep chats about our relationship with other women I’ve never even heard of.

He’s showing real accountability and wanting to change after getting caught. But do I trust it? Do I see where this goes. How do I know it change is going to hold?