in my opinion it's not that easy to decide, there is difference if it is BF or husband and there is difference in husband case if there are any children or no. initially any person will reply "move on" but my reply is conditional
"if he is BF then move on
if he is husband and no children then count to 100 before deciding to move on
if he is husband & u have kids from him then waiting for ever is better than destroying the family"
finally, u should consult some experienced ppl "e.g. ur parents" for such decision to avoid regret in the future
good luck