Transfer from joint to single person mortgage advice

Bigsy_2

Just after some advice before I go speaking to the mortgage company on Tuesday.

My situation: Partner and I have separated (not married), she wants to walk away from the mortgage. I'm not sure what to do.

I put in 20k, she put in 8k, on a 10% deposit, the house has dropped in value and as a rough guide I'd say if we sold we could payback the mortgage but lose the deposit money. I don't want to do this it took me years to save every penny of that 20k. Her parents gave her 8k so shes happy to let that go, but did ask if I could pay them back in time.

So the other option is to take on the mortgage myself, its about £1200 a month I take home £2100 after tax so I could probably do it, maybe get a lodger if it gets tough. But what will the mortgage company likely make of this? As if I were applying for this much money as a sole owner I don't think they would lend me it.

What to do if they don't? Is there anyway I can take on the mortgage, keep it in joint names but stop my partner having a claim on any potential profits?

Will a change from joint to single constituent a change in owners? Will it me libel to stamp duty?

Any advice greatly appreciated, this is the first time I've been through anything like this, in fact I was a first time buyer as of about 6 months ago... not a good start.