James,
I'm sorry to hear you are being messed around by the NHS. It's a tale so many on here and elsewhere will understand when it comes to mental health (and physical health).
I would take that anger & frustration and do as pulisa wisely says. Don't play into their hands by acting with violence (whether to people or property) because they will just regard you as someone unstable and kicking off. They will reach for the meds to stop that and not care about why you got there. Take all this and get behind your complaint. Demand action and show them all their errors. They won't be able to explain many of them and they will squirm into trying to steer the conversation away from their failings.
Will you get anywhere with the NHS in terms of change? Highly doubtful when there are so many much bigger systematic failures they try to wriggle out from under but you can add to the voices. But more importantly you can use this as a reason to make them take action rather than brush you off whilst they firefight some other issue elsewhere with someone else. Make it a complaint and take it beyond the fob offs of a nurse on the phone.
It would be worth your partner doing this too. They can dismiss you as unbalanced & irrational but they can't do that with her. And she should be pretty annoyed that they have assessed her as responsible for your meds to now say the opposite, something which seems at odds with their care remit when they have been giving you meds before. It's full of holes and shows their management to be pitiful.
I think your GP should also be pulled into dealing with them too. GP's are very fond of sitting back once someone is referred but they remain your primary care professional and we should use them to chase up remote professionals who see us more as numbers. Make them work for their money!