Helping Puppies Learn to Be Alone

When puppies arrive home at 8 weeks they often are in, or just starting, their first fear period.
If you expose a puppy to isolation and they get scared and do not recover, then they can become conditioned to being fearful when alone. These puppies can develop separation related problems and it can be difficult to overcome them. (O'Heare, 2004)
A puppy's mum at this age would still respond to her puppy's stress calls, it's not normal for them to be ignored. They are vulnerable and need to be cared for.
They do 'following behaviour' at this age because they need to stay close to their family to survive, because they are not old enough to fend for themselves.
My puppies are not be left alone at night for the time being, they stay with us but in their own bed. They have an area for sleeping and an area for toileting. The crate is open. The toileting area must be away from the sleeping area, not in the crate. Crates are sleeping areas only.
Some puppies naturally settle really well alone at night alone and some don't.
If you have a needy puppy it is better they learn to be left alone during daylight hours in a structured manner and I will condition positive associations to this and increase duration as they cope.
This is an important time for you and your puppy to bond. If they need you, be there to support them.
The key to coping alone is about attaching emotions of relaxation and safety.
Start by giving your puppy something to do like a stuffed kong or chew and then leave them.
Chewing is relaxing and calming so can help with the right emotion.
Return shortly before they have finished and try be cool and calm so you returning isn't too exciting. Just return to the room and go about your daily business.
Lots of little short bursts of you leaving and returning.
You leaving and being in another room is often harder for them that you leaving the house and them being unable to hear you. Being separated from you and being able to hear can be frustrating.
When they are tired and settling down to sleep try to encourage them to get in their crate to settle. This routine will attached sleep and relaxation associations to the crate.