I have two very nervous rescues one can be off and on with housetraining and they have to stick to a strict routine otherwise they get a bit stressed. Animal angels dogs sitters were great they visited first to see you and the dogs and whole I was away they gave regular texts and only lead walk them, very nice to deal with cost us 450 thought but kennels were not an option our two would have been really stressed etc
What about googling your local Sussex dog rescues and discussing it with them. They may know of people who would do this... presume you've already asked family/friends and that didn't come up with a solution. Ringing the local dogs trainers, as Hercy said, sounds like a great idea.
Can she be left alone for a few hours at a time? If so it might be worth ringing round local trainers who do house sitting as well. The reason I ask about hire being left alone as most trainers who house sit often do dog walking as well - often in groups, which wouldn't be appropriate for your dog from the sound of it. So they would need to leave her while they do that. The positive is you'd get someone experienced with dogs with all kinds of issues.
Might be worth looking at some local tutors through here...
Please don't write off all kennels. Some kennels are excellent, and really do go the extra mile, and many are very used to the issues posed by dog aggression and continence problems. At the top end of the market you are looking at doggy hotels with individual suites so very much calmer and quieter. I actually paid a social visit earlier today to the main kennel we use - the lady who runs it also provides space for rescue dogs and is superbly knowledgeable and very hands on. Our elderly and reactive dogs recently stayed with her and I knew they were in incredibly safe hands. They had made special arrangements to put the two grumpy old men in a quieter block away from the main area and they were walked/exercised separately, which is often normal in kennels anyway.
You might also find that if your local rescue has kennels (not all do) they may be willing to take in a holiday boarder - I know several greyhound charities who do this.
What do you do when you go away and can't take the dog?
We usually only go on holidays where we can take our dogs with us, but are going to a wedding in October and will be away for 4-5 days.
She is incontinent and dog aggressive but will sleep on an incontinence pad and can be walked either on lead or offlead where you can watch out for other dog (she has great recall).
I'm wary of kennels as I think her aggressive issues came from when she used to go to day care at the local kennels, and I don't know anyone who coul come and house sit (though I am open to house sitters).
I'm sort of hoping that there is a high needs dog sitting guru around whose services I can enlist! Any ideas?