Sorry if this is long but I want to give as much context as possible.
Our dog is a border collie x. We got her near the end of 2019 from the rescue when she was around 2 and a half years old, so she's around 9 now.
When we first got her, her big problem was reactivity to other dogs. The reactivity was excitement-based rather than fear-based: she'd lunge on the lead at other dogs and get very wound up, but she wouldn't bark or cower from them or anything like that. Thanks to training though she's gotten a lot better over the years.
She had no problem with people though, even strangers. She would love when random people on walks wanted to pet her or when people came into the house. That changed probably around 2-3 years ago when she had 1 bad vet visit. The vet took her into a room so we couldn't see what was happening, then the following week we had another visit and she was completely terrified, trembling etc., and the vet was quite heavy-handed with her. We didn't think much of it at the time because we just changed vets, and lots of dogs are scared of vets, whatever.
But then we noticed she was scared of strangers in general. It's fine if we're just walking past them on the street but if they go to talk to her or pet her she recoils away from them, and kind of turns her back on them like she doesn't want anything to do with them. She also started to bark at strangers (e.g. tradesmen) coming into the house. Our way of dealing with this was just telling them to ignore her, which worked pretty well. However one time we hired a dog walker who didn't ignore her, tried to talk to her etc., and she was barking at her and actually started trembling — but then warmed up to her after about 10 mins.
The other thing to mention is the fireworks at Halloween time. We can't really remember what she was like with the fireworks when we first got her, but in the last few years we've noticed she's been quite scared of them. When she hears them, she kind of just cowers up next to your feet, and sometimes she'll even sneak into the bathroom and lie in the corner. We had heard of other dogs who completely freak out from fireworks so we considered ourselves lucky.
Now, finally we get to the important part lol. A few times when walking her around Halloween time, we'd hear a firework go off in the distance. She'd instantly get very scared and refuse to walk any further, digging her heels in the ground, and even just completely lie down until we turn around and head back home, and sure enough she would walk really fast and pull us on the end of the lead all the way home. Whenever this would happen we'd think: fair enough, fireworks are scary, and there's no point trying to force her to continue the walk when she's scared and doesn't want to go. So we'd just head home.
But then something weird started to happen: sometimes when walking her she'd get this same fear-response as if she just heard a firework, even though we didn't hear one. At first we thought maybe she's hearing them when we can't (this would have been around New Years), but then we were pretty sure there were none gong off. And it would happen very randomly and at very random locations; we started to think it might be various noises like cars going by, car alarms, just weird noises in the distance?
These fear-responses would happen more and more frequently and now, as of writing this, my dog can't get past the front lawn of the house without getting scared and refusing to walk further.
I want to try give as much detail as possible: at first we thought it was certain locations she was scared of, but then there were some days where she wouldn't react to that location at all, but a different one. Before this week, we think there was always some kind of sound happening when she started to get scared, even if it was just a car going by, but now in the last 4-5 days there's definitely been no sounds that could have caused it. She also has no problem going out the front door to begin with, but once she's out there she'll get scared at some random location (and this location has gotten closer and closer to the house over time).
When I google solutions for this problem a lot of it seems to be about finding the "trigger" and desensitising her to it through treats. The problem for us is there is no clear trigger; it happens very randomly. It's as if the fear just gets into her body from nowhere.
I want to mention one other thing: my mum got a soup maker for Christmas and she's scared of that too lol. Now fair enough it's quite a noisy thing, I'd be scared of it too, and if the problem were just that she went upstairs away from the noise then that would be fine. But no: she'll actually refuse to come back downstairs for hours and be afraid of the kitchen entirely. A few times she has asked to go out the back garden and she actually hid in the bushes, and it can take a while to get her to come back in! Thankfully so far we've been able to coax her with high-quality treats, but still, it definitely seems like she's a bigger scaredy cat in general than she used to be.
Anyway, for the past 1 or 2 days I've been trying to fix this by taking her out on a walk like normal, and once she gets scared (which at this stage is only a few metres from the front of the house) I started giving her high-quality treats, getting her to sit, lie down etc. She's able to follow the commands well enough, but she still has no interest in actually walking, she just wants to go home. I've tried walking a few steps in the direction she doesn't want to go and then getting her to "come", and I've been able to get her a few yards down the street that way, but it's not really a walk lol. Sometimes I'll get her to "come" and then as she's coming towards me I'll take a few steps back, and she hesitates, as if she knows I'm trying to "trick" her.
So to finally wrap this up: the most immediate problem is her refusing to walk, but there's also the worry that she's just become a big scaredy cat in general. It makes us worry about people coming to the house like tradesmen, since she's already barking at them and her fear seems to be getting gradually worse over time.
Any advice? Is there anything more concrete I can do other than just coaxing her down the street with treats? We were thinking of desensitising her to the soup-maker in the hope that it might improve her fear in general, but there's a worry it might just improve her attitude to the soup-maker and nothing else lol.
Sorry this was so long 😭 Happy to answer questions if more details are needed