Between gulps of G&T, my heartbroken friend is cataloging all the things that are wrong with her freshly ended relationship: his emotional immaturity, her unmet need for stability, and then the kicker:

“I can’t commit to someone who doesn’t bloody recycle!”

I ask her why. Because his time and energy was worth more to him than other peoples’, because he didn’t care about the world he left behind – and because she couldn’t stand the guilt of being with someone like that.

Environmental guilt is a very common response to conscience but the sheer scale of the earth’s problems – climate change, ecosystem decay, pollution and animal extinction – can create a kind of mental paralysis. I once stood in the produce aisle for fully five minutes, tossing up whether it was more environmentally sustainable to take a plastic bag for a handful of pears, or risk them rolling under my other groceries, ruining them and forcing me to wash my canvas shopping bag.

The trouble is, the more I know about environmental degradation, the more complicated my lifestyle choices become and the more urgent the problem seems in my mind. I have taken on what psychologists call collective guilt, which keeps me vigilant. But might it also be keeping me paralysed?

On the surface, it makes sense. Like the Dutch having inclusive and even-handed foreign policy to make up for the actions of their colonial ancestors, we feel a collective responsibility for the mess our earth is in. And that should spur us to action, yes? It does – but only to a point.

A team of researchers for the Journal of Environmental Psychology found guilt a useful motivator in a group setting.

“People who experience guilt want to undo their actions, apologise and be forgiven,” N.S. Harth et al wrote.

But they warned that it was a state of dejection and therefore had low action potential, so was only useful when directly related to the remedy. You make a mess, you clean it up.

“Guilt about environmental damage does not motivate general pro-environmental tendencies but is closely linked to environmental behavior that aims at repairing environmental damage.”

See, it is logical for guilt to prompt us to act but in the long run, human behavior is not so straightforward. As a philandering wife is more affectionate towards her husband because she feels guilty, so we do our bit to try to smooth things over and assuage our guilt without dealing with the underlying causes. The guilt complex is called introjection; and some psychologists say it is unsustainable.

Canadian psychology researchers Richard Koestner and Nathalie Houlfort found that people who recycled out of guilt were more likely to have attitudes that wavered and behavior inconsistent with their attitude.

“To engage in a lifetime of environmentally friendly activities, it is important that individuals develop a motivational style based on true integration, rather than introjection. Recyclers must feel that they are doing it because it is personally important and related to their values, not because they feel guilty,” their study says.

Ironically, the more catastrophic you believe the problem to be, the less likely you are to feel bad about it. A US-Canadian review of psychological studies found those who took the most action were those who accepted that climate change was caused by humans but who thought the impacts would be relatively minor.

“Collective guilt is more likely to be experienced when people believe that global warming will have minor effects than when it will have major effects,” the report says. “When people believe that the harm produced by global warming will be catastrophic, then there is less sense that repair is possible, reducing the potential for collective guilt.”

“(It) suggests that the experience of collective guilt depends on a sense of collective responsibility for harm done, as well as believing that repairing the harm is possible,” the study says. “When people are frightened, they might be more motivated to deny a hazard than combat it.”

N.S. Harth et al also looked at anger as a motivator and found that although it was useful to give people the energy to fight for justice, it was no more useful than guilt in promoting environmental protection.

So you’d think pride would be the answer? Perhaps we in the environment movement need to focus on the wins we have had and the joys they have brought us. The psychologists say yes, but with a caveat: don’t be a dick.

A fascinating study of football teams in the 1970s found an interesting dynamic among ingroups called “basking in reflected glory” – that is where a group takes responsibility and pride in the achievements of others. So while we bask in the glory of environmental wins across the world (such as a successful carbon trading schemes in Europe), we feel connected with them and that fosters our commitment to the movement. But new studies about the environment movement have found the dangerous flipside is that feeling of kinship can be exclusive. Anyone who has sat through dinner with an environmental zealot can attest.

The environmental in-group, in the process of basking in reflected glory, can make decisions that will aid only their own group, to the detriment of others, N.S. Harth et al said.

Depressed? You’re not alone. But don’t despair.

The benchmark for behavior studies, Deci and Ryan’s work on self-determination, has excellent guidance for the environment movement. People need to feel free to make their own decisions and are motivated by personal value and enjoyment – this is called internalized motivation. A 2003 study put Deci and Ryan’s studies on an environmental framework and found that positive internalized motivation of this kind was a potent way to spur people to pro-environmental behavior. That’s because having positive feelings about our community’s capacity to manage environmental problems makes us more likely to change our own behavior and to advocate on behalf of our peers.

With the scale of the problem constantly in our view, it’s easy to forget how far we have come. When I was a kid, everyone I knew was driving a gas-guzzling car, failing to appreciate or invest in public transport, spraying CFCs, cleaning our driveways with town water and gobbling plastic bags and cheap plastic toys.

Of the 10 things LiveScience identified as the environment movement’s “craziest” ideas in 2008, more than half are now public policy across the world. Sure, atmospheric sunglasses didn’t go into production but among those lampooned were also the plastic bag ban, cutting and capping carbon emissions, recycling trash into building materials, carbon sequestration, and widespread compost schemes.

My city, San Francisco, started phasing out plastic bags back in 2007 and is now investigating a bottled water ban.

 Both would have been unthinkable without the groundwork done by the environment movement in previous years, and the pride that San Franciscans take in having a livable city.

And my friend? She and her new husband are happily settled in a little Tasmanian town with their six-month-old son and a kitchen garden. I am happy to say they both recycle.