I first met David Cameron in 2006, during a period when the Tory party was moving towards the more caring and compassionate image described as One Nation Conservatism. At my invitation, David Cameron – then leader of the opposition – visited a centre in East Sussex at which I volunteered some of my free time to care for people who were homeless, or living with severe and enduring mental illness, many of whom also had substance misuse problems. On that day, I was genuinely impressed with his clear personal commitment to improving the lives of some of the most disadvantaged people in our society. He talked of “broken Britain” and of better supporting people who were in his words: “the victims of state failure”. It was after that meeting with him that I was persuaded to enter representative politics, as a Tory.

The past year has shown me that Westminster too often feels a world apart from the reality

During my time as a health minister in the coalition government, I continued to work, on a part-time, unpaid basis, as a doctor in women’s health. Then, just under a year ago I made the transition to working in NHS mental health services. Twice a week, I look after a very vulnerable group of patients who are not only unwell, but often face some of the most appalling housing and social circumstances. The results of that are revealing.

As I reflect on what has changed since that meeting with David Cameron in 2006, I struggle to see much improvement in the situation of some of the most disadvantaged people in our society. They are still the people that politicians tend to forget. Chronic underfunding of mental health and social care services, a shortage of social and appropriate sheltered housing, together with a benefits system that does not always adequately recognise the needs of people with severe and enduring mental illness do not help. The increasingly fragmented health and care landscape, coupled with the loss of many vital specialist substance misuse services, has made the situation worse.

The past year has shown me that Westminster too often feels a world apart from reality. It has also reinforced the belief that the state, and the people who work for it – in the NHS, in local councils and elsewhere – remains a tremendous force for good, that can touch vulnerable lives for the better.

Take Jessica (not her real name) who has a recent diagnosis of a severe mental illness and is sleeping on a mattress in her flat in London because her landlord repeatedly refuses to sort out the damp. She has two children, debts approaching £2,000, and resorts to food banks because she can’t properly feed herself on her benefits. Jessica’s main and only help comes from a specialist community mental health team and a dedicated care coordinator who acts as a negotiator and intermediary between her and various debt agencies and council services.Take Jerry (again not his real name). He has been diagnosed with a severe mental illness, and has a personality disorder. A young man, he is struggling with substance addiction and has little prospect of employment. Jerry has been living in a hostel for six months because there is no suitable available housing. He has been under the care of a community mental health team for almost two years.

Despite recent commitments to marginally increase spending on mental health in the future, NHS funding for mental health services in England fell from 11.17% in 2008-9 to 10.67% in 2013-14 of total NHS spending. Patients are being cared for by a chronically underfunded system. The benefits system, with its tick-box approach to the physical ability to work, continues to discriminate against people with mental ill heath, and particularly those with more complex mixed physical and mental ill health needs. Current housing policy, and a lack of social, and supported housing, also makes it difficult to care for people with chronic and enduring mental ill health.

The government has rightly committed to balancing the books and eliminating the national deficit but the challenges facing Jerry and Jessica, and many tens of thousands of other people, makes it all the more important to ensure that financially responsible government also means compassionate government. Our first priority must be to look after and protect the most vulnerable, and the genuinely disadvantaged. When there is so much still to be done to improve the life chances of the most vulnerable, it is difficult to justify putting middle-class tax cuts before the needs of the working poor, and the socially disadvantaged.

If we are serious about improving the care and the life chances of the most disadvantaged people in our society, we must properly fund, and join up, the many agencies and services that care for them. This also requires a benefits system that properly supports those with mental ill health. If we want to fix the “broken Britain” that the prime minister identified, then there is still much to do. Away from the gleaming spires and debates of Westminster there are no private sector care providers, just hard-working NHS teams, a few volunteers, and many other dedicated public sector workers doing their very best for the vulnerable and marginalised.

The people Cameron met in 2006 were only the victims of “state failure” because the state was not properly resourced and too fragmented. Improving the plight of the most vulnerable requires a political debate that better values the state as an important force for good. It will require more money and resources, and also a belief and commitment to prioritise investment in our NHS and our local councils who are very often their only source of care and support.

Perhaps the fundamental truth is this: that truly governing for one nation also means caring about the state, and recognising its power to both protect and to transform the lives of the most disadvantaged for the better.