Apologies for the long post, I probably need to give a bit of context.
DH and I together for 10 years, two children aged 5 and 3. We've always had similar views on political and environmental affairs - in particular about global warming and how we harm the environment in other ways. He's taught me (and I'm grateful for this)to be far more environmentally responsible than I would be otherwise. We buy local (failing that British) stuff where possible. We're very aware of the plastic packaging problem and make choices bearing that in mind - we recycle virtually everything we're able to (sometimes at a cost) and we find other uses for stuff rather than throwing it out. The kids get what they want for Christmas but we don't get them (or each other) "stuff" for the sake of it. I use a car (necessary for my work, not his) but walk and use public transport a lot more than other local families - we are saving up for an electric vehicle. We've invested in extremely expensive solar panels on our roof.
Anyway, in part fuelled by the possible economic meltdown that we're facing with Brexit (another thing we're worried about but it's kind of out of hands for now anyway), he's been worrying about the planet a lot more of late and is now pretty convinced that 10-15 years from now (and certainly in our kids' lifetime) life as we know it will end. Global temperatures will rise to create catastrophic weather events and global crop failures. Oil will simply run out. There will no longer be enough to eat; there will be widespread famine and everyone else will be rioting in the streets.
He's a very intelligent man and reads well-researched books and articles on the matter, he's not crazy. His views are however I think at the extreme end of things. I think, possibly like most of us, that global warming is a very serious problem that threatens us all. However I believe that eventually, sadly probably after some other very sad weather or agricultural-related event, world leaders will be forced to act properly rather than dithering. And although global warming cannot be stopped, it can be slowed and its effects will be mitigated. Meanwhile technology will catch up and the world will finally start using renewable energy sources far more so than they do today. I can already sense a bit of a step change in the way British people view things - over the course of the last year people are stopping using throwaway plastic bags, cotton buts, palm oil etc. All teeny steps but they add up and eventually these things will snowball and the whole world will have to stand up to the problem and work collectively to mitigate it. And if it all does go to pot then it's probably further in the future than he thinks. That's my personal view, possibly a bit naive but I've always been a glass half-full sort of person.
He thinks we all need to act today. We need to become vegetarian (he has become one, and thinks I should 'search my conscience' when deciding if I should as well), we shouldn't fly anywhere again ,we need to pare-down our already pared-down Christmas. We need to start stockpiling food. We shouldn't buy anything at all that we strictly don't need. We need to stop using gas to heat the house and put the log burner on every day instead (a nice idea but not very practical). We even need to stop streaming stuff on the internet because it's so energy intensive.
To be honest I don't have the head-space to deal with all of this right now - I have children to look after and a relatively new small business to run. But I can't live with the constant doom and gloom and am now questioning our relationship seriously. We always (I thought) shared similar views but I never subscribed to his catastrophising. I am happy to listen to him 'vent' to a point but there's a limit to how many apocalyptic scenarios I can take. I honestly don't think he's mentally unwell, everything he believes in is probably true, but at the moment I am totally unsure what to do next because I can't deal with it. I'm wondering if some professional help is necessary, not to 'snap him out of it' but to help him come to terms with what is happening and help us hopefully lead a relatively normal life once again. And maybe to help us find some kind of middle ground that can help us move on.
I'd be really grateful for any thoughts on how to handle this.