Dear Kobuk,
In my opinion, and assuming your dog has no medical problems causing pain, your dog may have taught himself how to gain attention from you.
Now the crying while pooping could be a source of real discomfort and a veterinarian's rectal examination as well as a pelvic xray study may be able to rule out problems that could cause pain with defecation.
Barring that, your best bet is likely to be obedience training. There YOU will be taught how to modify your dog's behavior, including terminating needy, attention demanding whining. To date, it may be that your dog has trained you to "assure him its OK" whenever he feels he'd like some assurance. That pattern reinforces this dependency you speak of.
I suggest you pursue a medical diagnosis first and then find a dog trainer and work with him/her to achieve the behavior patterns you desire. Often a needy dog given a job...a chance to perform for praise...will be better adjusted and less demanding.
Good luck to you.
Dr G
Thank you so much! I guess that I'm the one who needs training. He does not have any medical problems, other than the crying.