Zsu.....I think the burden you are complaining is more emotional than physical and the attachment he is showing to you is more neurotic than normal.
Sorry , i hope these words dont offend you...
It seems both of you had developed this closeness as a coping mechanism to face the reality that he doesnt have a father and you are alone in raising him....
If it would be only a matter of simple physical problem a talk with him at his eye level and some persistency in your behavior would fix it...
My daughter was pretty heavy too...i mean, she wasnt fat but it looked like her bones were filled with cement...lol....i explained her that i couldn't pick her up anymore like before...but naturally i didnt stop hugging her and let her seat on my lap ....
Problem is your son might fear to lose you if he allows to the two of you a bigger distance....he is insecure...and surely you yelling at him must have convinced him even more that you actually really dont want him close. I am sorry...its a delicate and painful situation but you have to be strong for him too.
I hope you can sort things out in yourself ....you are the one who needed him so close to you and inconciosuly shaped the relationship...kids absorb our emotions.....you are the one that have to let him understand you will keep always loving him even if you are not hugging him 24 hours a day...
Also i sense some guilt in you toward him....dont be...i am single mother too...its hard sometimes...we want only the best for our kids and sometimes i feel like a failure for not having been able to keep her father with her...
But these are unfair thoughts...
He is young...he will adjust to your new way of loving him..just keep loving him. Its all it counts....good luck...:-)
Zsu....i am glad i didnt hurt you with my guessing...;-).
your little one is comfortable with you and love you very much...its so sweet....:-)
And i agree with Secret....he is still young.... he can still have some deep closeness as long he understand when its too much for you.....the peer example migth be useful......
You will see...in a little while you will have to ask him to crawl on your lap...they grow so fast.....:-).