The only way to get over your past experience is to work on the present. You don't need to abide by any timeline, you go at your own pace. Maybe he's not the one for you- you won't know until you try dating and honestly, if you do end up only wanting a friendship, it's only fair that he finds out sooner than later. He's afraid if he waits too long you'll end up losing interest and wanting him only as a friend. He doesn't want to put in a lot of time to end up hurt. That's all he means.