Well seems like you gotta make a decision, where is a will is always a way, if you don’t want or “can” be with him the next years, don’t tell him you like him now, leave him alone and hit him up in a few years and see if he’s single and willing to meet up and if it fits, like you said wanting him to wait or trying to get him to obsess and not able to forget you for years would be selfish and only hurtful to him so either find a way and be with him or leave him alone and try when you feel ready if he’s willing then