Separation anxiety?

Question
Good Morning, Please help me!  I rescued a yellow lab from neglectful home-he had food but no human touch, no shelter to speak of and most likely was hit by the owner-he squints his eyes if you move quickly around him.  I rescued him because he had jumped over a chain link fence, gotten caught and was actually hanging-only his back feet touching the ground.  So, I'm a Lab person anyway-no other breed in the world to me :-)  My rescue is approx 12 mos old, I've had him 3 weeks, had him neutered last week and he was diagnosed with level I heart worms.  He will be treated for heartworms in 3 weeks when he recovers from the neutering surgery.  Now, my question: My rescue rushes the door when I leave.  He began by actually crashing the door, scooting out past me and just howling.  I've pretty much remedied that by patience and Kong treat toys, but now he has outsmarted me.  He now knows that when I load up the Kong toys, I'm going to work so he goes outside and I have to demand that he come in.  Once inside, he ranges in reaction-he will either crash the door and I have to actually hold him back or he will stand in front of the door and I cannot exit...help, help please?  I love him dearly and want desperately to feel loved.  I do not hit animals and don't agree with the "old way" of training-by hitting, etc.  I would love to break him of this nasty habit before we both suffer further.  I assume he doesn't want to left alone b/c of the neglect in the past?  I've implemented the following, and they have helped, but no magic bullet yet:
soft background music,toys,work toys (kongs loaded w/treats)food in bowl, articles of my clothing for bonding/snuggling, opened blinds so he can see out, etc.  I cannot leave him outside for my work hours, I'm afraid he would hang himself on my fence, as he did at the neglectful home....please help?  I don't want to give him drugs but I'm afraid it may be my next stop!

Answer
Well, bless you, Caren, for taking this dog in!

To my way of thinking, rehabilitating him will be much the same as for a puppy mill dog - time and patience.

First of all, I would teach him to accept being in a crate.  This way he'll be safe while you're gone.  If you get him in the habit of going into the crate, you can put him in before you go to work, and he won't be able to rush the door.

If he starts to figure out your routine, that he goes in the crate and you leave, you'll have to vary things to keep him guessing.  Don't just put him in when you leave; put him in when you eat, or for other brief periods during the day.

It will take him time to start trusting again.  We just brought home a female golden who was a puppy mill breeder dog.  She's extremely timid, but in the 2 weeks she's been with us, she's improved noticeably.

Setting routines and schedules will help him feel more secure eventually.  Being a kind, gentle "leader" will help as well.
Here is some information for you to look at:

http://www.ddfl.org/behavior/crate-train.pdf

http://www.ddfl.org/behavior/fearful-dog.pdf

http://www.ddfl.org/behavior/nilif.pdf



P.S.  Thought of something else:

http://www.ddfl.org/behavior/sep-anxiety.pdf