Separation Anxiety & Crate Training

Hi everyone! I have an almost 5 month old Labrador that I rescued at 15ish weeks who is amazing in a lot of ways. He is great on a leash, listens pretty well for a puppy, doesn’t bite much, etc. Overall he’s a total sweetheart and going to be a great dog.

However, he has horrible separation anxiety when I leave the house. In terms of his crate, he seems to be indifferent to it. He willingly goes in there to sleep at night, will eat his meals there, and will go if I tell him to for a nap (with some whining when I leave the room). The crate is currently in my bedroom because if he can’t see me he won’t be able to fall asleep. Anyway, the biggest issue is that when I crate him and he hears me leave the house, he lasts about 10 seconds before barking and whining. I have been “leaving” 3-5 times a day for a strict 60 seconds for the last 2 weeks and it hasn’t gotten any better. I was planning to keep doing the 60 seconds until he got better then move to 90, 120, etc., but he doesn’t seem to be making much progress. Does anyone have any advice on what to do here? I feel like I’m losing my mind and want to be able to leave my home!

Some things to note: – I live in an apartment and received a noise complaint when I left him for an hour (I didn’t know he was barking and whining) so I want to be careful about his barking but also need my life back and want to be able to leave my home! – He does fairly well when I go to shower, use the bathroom, etc. but he just always wants to be around me, but sometimes whines (I can also hear him walking up to the doors when I’m in another room). – He had a foster parent before me who kept him in his crate in the dark in a laundry room when they would leave and at night, so I wonder if he has some trauma from that? – I have seen some improvement with him being alone in another room, in his crate alone, etc.