My girlfriend of four 1/2 years has just dumped me, mainly because of anxiety, help?

I have been with my girl for four and a half years,and all has been fantastic for the entire time. However I have had anxiety, ocd and depression for this duration. It has improved massively, but Ive failed to meet promises and fix things, and I realise this now its too late, of course. Trouble is I thought I had forever to make improvements.

What can I do? I know she loves me, and I want to improve.. but she's felt "drained". I really believe if given another go I would be able to fix things and be the man she loves and had these good times with.

Problems were obvious anxiety based, but like I refused meds and tried naturally, maybe I should of tried that..and little things, she wanted us to be engaged, live together and for me to pull my finger out (eg I have slept on my couch in my 3 bedroom house for 4years) and trouble is I promised all this and more, but now realise I made it impossible..eg saying I'd buy a new bed, move to certain new houses and only buy expensive engagement rings (although we've both been ready and she said £100-£200 more than enough)..so basically I was stupid and naive and wanted to drop like £6000 to make this all happen, and all without a job (finally got one)..but now I've realised it was stupid to say id do this that and that when it was impossible.

I could of basically said yeah ill commit to you when an aligator eats a turtle in my back garden, because i was that stupid. Trouble is I really thought I had years to make these changes.

With all of this and anxiety combining, what steps can I take to get her back/improve? Any advice please?