You’ve got a teenager. And a diva!
To go straight to point 2, and horses. My neighbour has two horses, and a public footpath through her field. All dogs should be on a lead where livestock are kept. The consequences of an accident are horrific. Yes a dog can get kicked, but a horse can bolt with disastrous consequences for itself, can be bitten, and generally be traumatised for riding anywhere. The law is on the side of the grazing animal and my neighbour has moved her horses out of that field because lockdown dog owners have caused too much worry for her.
Point one is a matter of patience, and better to do more shorter walks than have a miserable long one. I sympathise, because my tiny poodle cross is an embarrassment as well if another dog is in sight.
Point 3 is the possessive Diva! I’ve not experienced it like this, but all I can think of at the moment is to let her unwind on the other side of a baby gate from you, with a stuffed kong to lick. You can’t have a crocodile when we have visitors again! My tiny pup blocks me from the iPad, they are like toddlers wanting mums attention, and a bedtime story. Teeth are the only way that works. They should really be settled by 8 pm, my cocker was out of it by 6pm, but he had an older dog to show the sensible behaviour. I think a routine of peace and quiet isoniazid the cards.
You’ll get there.