I'll try to keep this brief, as it could otherwise be a lengthy saga.
Basically, the relationship between my mother and my mother-in-law has broken down to the extent that they won't be in the same room as each other. I'm at a loss as to how to try to fix things or whether I should even try.
My mother is Mrs Negativity. She finds fault with pretty much everything as just part of her conversational style. She doesn't even realise that she does it much of the time and if you point it out she says that she doesn't mean to be critical. She almost certainly has been depressed for most of her adult life but has reacted really badly to anti-depressants in the past. Some CBT therapy has helped with targeted problems but not her general negative approach to life. She is also going through a difficult time. My father died nearly 3 years ago and they had been together nearly 45 years. She is facing moving out of the home they built together and lived in for most of that time. She professes to like change, but without a doubt finds the process of change very, very difficult- even for small differences. She is also struggling to come to terms with physical disability that is preventing her from doing lots of things that she planned to do after my father died.
My MiL is generally an anxious person. This mostly manifests itself through disordered eating and health anxiety. COVID has exacerbated this, party rationally as she suffers from brittle asthma and gets frequent chest infections, but partly due to her anxiety. She is an emotional communicator - when she talks it is always about people she knows and what they have said and what they think, or she will say something that might not factually make a lot of sense but is important to her for the emotional impact. But for all her emotional connections she can be quite unable to see things from someone else's perspective and can end up being pretty tactless at times.
For COVID driven reasons, I, DH and 2DC have lived with my mum since the beginning of lockdown 1. DC2 was born shortly after this started and because of lockdown MiL hardly saw us for about 3 months. She was understandably jealous of my mum for this, and for the close relationship that my mum now has with DC2 in particular. Now I'm returning to work and we are reliant on MiL for childcare, which she has offered us two days a week. My mum is jealous of MiL as her disability means she is not physically capable of looking after the DC on her own for more than an hour or so.
I've developed a pretty thick skin when it comes to my mum. I mostly shut down or ignore her negativity and it only occasionally gets to me when I'm stressed about other things. I find MiL's anxiety and emotionality quite irritating and for a time our relationship was not good - I would deploy my defensive shutting down tactics which really made her emotional neediness react and upset her. I've tried really hard not to be so defensive and things have improved somewhat.
Things recently came to a head when MiL got upset at one of my mum's negative comments and accused her of being ungrateful for a lot of hard work that my DH has done on renovating a bungalow that my mum is shortly due to move into.iL got so angry that she apparently stood there shaking her finger at my mum and scolding her like a child. My mum has decided that she won't be around MiL unless absolutely necessary as "It's not fair to her to have to be around someone about whom she has such a low opinion".
I believe that both mum and MiL are kind people who want the best for their families and will put themselves out see that, but they are both quite flawed in very different ways. I don't know whether to let things lie- to accept mum avoiding MiL and refusing to join in family meals, or to drag them off to family therapy in a hope that they might actually find a way to get along. They are both in their 70s so I'm not hoping for any radical behaviour changes from either but it would be nice if they would work together rather than tearing strips off each other.
Is therapy a good idea or should I just ignore the rift and accept that things are better if they don't spend time together.