Around 90 days.
Scientifically speaking it takes 90 days to clear all love stuff from your mind if you do not keep it revising!
21 days to break habit. Cut all connections and wait for three weeks. Don’t revise her letters, chats, messages, photos and every thing.
After successfully completing ‘no contact ‘ period of 90 days it is better to start a fresh. Before that you decision will be judgemental.
But dude enjoy being single for a while. Singles can pair but doubles can only un pair!
PS: I am strongly against rebound love unless girl reinitiates. This is always counterproductive and complicated.