Before Christmas, a woman came to see me in my constituency office in Barnsley. She has three jobs and is still struggling to pay her rent, let alone afford her own home for her family.

I thought of her again when I heard David Cameron’s claim that we are in one of the great reforming decades. His government has demonstrated neither the will nor the capability to make that a reality. Only Labour, with the huge increase in our membership, can build a national movement of all classes to lead the country into a great age of reform and social renewal.

The Conservatives promise a living wage while planning reductions in Universal Credit. Their welfare reform claims to create opportunity for the disabled but doesn’t support employers in providing jobs. They champion the march of the makers but cannot create the right conditions for investment. While they implement their Northern Powerhouse, their policies wreck local government. Their model of economic growth is overly dependent on personal debt, consumer borrowing and asset bubbles. They have no alternative to an economy that extracts wealth rather than creating it and that replaces middle-income skilled work with low-paid, low-skilled jobs.

The social cost of these choices is huge. Too many families are underpaid and overworked. The talents of millions of working people are wasted. Training and vocational education are neglected. Social mobility has ground to a halt. There are still close to 900,000 young people who are not in education, employment or training. Now George Osborne warns us to prepare for another downturn, but just as they have neglected the flood defences, the Conservatives have done nothing to protect society from another economic deluge.

Until Labour accepts the lessons of two successive election defeats, however, we will not renew our politics and reconnect with the public. During the election I campaigned up and down the country. People frequently told me that although they knew the Tories were unfair and represented the interests of the better-off, they did not trust Labour with their taxes. We have to win back their trust.

That’s why we need to publish our official party inquiry into why we lost. Once we understand that we have been out of step with the electorate, we can start to build our political recovery and respond to the policy challenges Britain faces.

Labour can help to build a more federal and democratic settlement both in England and across the UK. Our Labour council leaders are showing the way; they are our front line. We can create a new model economy that is pro-business and pro-worker, that combines financial realism with economic radicalism – an economy of wealth creation founded on partnerships, reforming institutions and supporting people to develop the skills, power and knowledge they need to achieve. That means strong trade unions that can play a part in rebuilding the country for the common good. And it means Labour becoming the party of the digital revolution, leading the future of technology and innovation in modernising the economy.

We also need a new model welfare state. Social renewal requires a just distribution of political power, wealth and income, and public services that are responsive and involve the people who use them in their design and delivery. People want a fair system of social security based on contribution. We need to invest to prevent social problems and not waste money on expensive, reactive and often ineffective services.

Finally, social renewal requires a more integrated society and tackling social and ethnic divisions. That includes the way we deal with epidemics of chronic conditions such as depression, obesity and diabetes. These are intensified by poverty, class inequality, poor diet, loneliness and the stresses of a society in which our sense of belonging is weaker and the ties that hold us together are looser.

Labour now has a new and powerful resource for the challenge of reform in the years ahead: our membership. Since Jeremy Corbyn was elected leader we have attracted tens of thousands of new members. By harnessing ideas and energy we can become a radical force of national renewal. But that means we have to find the courage to reform our own organisation.

The branch meetings and committee meetings that worked for us in the past don’t now. Our old party structures need to change and become more flexible. Tom Watson, our deputy leader, is working hard to make Labour a party of the digital age. The internet plays an important role helping people who are busy juggling kids and work to engage with the party. Social media attracted many of our new members into the party and will be essential for keeping them engaged.

But we need to make sure that our members can contribute fully, beyond the odd online poll. These short-circuit institutional checks and balances on those in power, they lead to poorly designed policy, and if they are conducted online, they exclude those without access to the internet. The party needs to build leadership and organising skills among our members to harness their talent and develop a more democratic party. The value of our members should not be counted by how many million conversations we have with voters. We need conversations that build enduring relationships with the public, not transactional cold-calling.

This year should be about Labour renewal: renewing our structures, politics, policies and how we work. The debate will be passionate and tough but we have a membership the Conservatives can only dream of.