D.I.
Sounds like he is going through the separation anxiety stage. He wants mom and that's that. It is going to take time and patience alot of patience but you'll get through it. He will outgrow it over a periond of time which varies. You can't give in and let him sleep in your bed no matter how long it takes for him to sleep because once they start they think it is ok to keep doing it. That is a bad habit for kids to get into because it is a pain to break them of it. If he has to scream and cry himself to sleep let him do it. Eventually he'll fall asleep. He'll be fine let him cry.
D.
I am 31 and have been married for almost 12 yrs. My husband and I have 3 boys ages 10,7 and 4.