Your girlfriend probably knows already that if she wants to work as a nurse in the UK she needs to register with the Nursing and Midwifery Council (www.nmc-uk.org). If she applies she must have been practising in the Philippines as a registered nurse for at least 12 months (full-time or the part-time equivalent) after qualifying. That would be a good reason for returning.
There is a 19 page booklet which can be downloaded from the NMC website, called "Registering as a nurse or midwife in the United Kingdom for applicants from countries outside the European Economic Area".
Once registered with the NMC, she can work in the National Health Service or private health, but the NMC states "We cannot help you find a job".
