This has unquestionably been a dire week for Oxfam and other NGOs, for all who support them – and for the millions who benefit from that. There is no exaggerating the dreadfulness of the allegations, or the way they’ve been handled – and the way the issue continues to be mishandled. But for loyal donors, what now? The answer: stay focused.

​In recent weeks decades of abuse in sport have been aired in court in the UK and the US. What has emerged is unspeakably awful, but should we respond by, say, switching our support from Manchester City, or preventing our children from taking part in activities they love?

This is a moment to remember that Oxfam has a proud history of standing up for the rights of women and girls, and against sexual abuse around the world. If refugees or displaced people need clean water and safe sanitation provided in a camp tomorrow, then Oxfam has the track record to deliver it.

This is about Oxfam, but it’s about much more than Oxfam, much more than aid. Wherever you find expats, whether from the UK, Belgium or Kenya, a few choose to exploit their privilege. The oil sector, the brewing industry, car manufacturers, airlines, cultural organisations, international schools – they have all had reasons to apologise for employee misbehaviour. Imbalances of power provide space for abusers. All those vulnerabilities need to be closely monitored.

Some public figures – notably the actor Minnie Driver – have understandably been quick to distance themselves from Oxfam. Others, such as the comedian Simon Pegg, have stood firm as ambassadors, expressing concern for those likely to be most affected by the backlash. Support has also come from some private-sector partners, such as the Unilever chief executive Paul Polman. Both are welcome.

The comedian Simon Pegg (pictured in the film Hot Fuzz) has ‘stood firm as an Oxfam ambassador’. Photograph: Allstar/Working Title/Sportsphoto/Allstar

Oxfam has work to do. It needs to deliver reforms to regain trust and to deserve public and private support, and has published an action plan to address abuse. But it remains to be seen whether its high-level commission will achieve the necessary culture change and public acceptance. Only the most rigorous reporting, investigating and addressing of sexual exploitation will convince supporters to hold their nerve. That’s a level of professionalism we expect of Oxfam, and that we must see again.

There are any number of worthy causes ready to receive your surplus household items, clothes or hard-earned pounds. But before you lose faith in Oxfam or in aid, remember that it is no accident that some have jumped on the organisation’s shortcomings this week: it has been done to undermine your confidence.

Of course it’s justifiable to feel sceptical, and it’s crucial that there’s change. But it’s also important to remember what aid is about, and why you give: and not to cancel the direct debit just yet.

• Lucy Lamble is executive editor of the Guardian’s global development site