Trigger warning in advance I’ll need to speak about baby loss to give context on this one.
I have 2 sisters: A and B.
3 months ago, B’s beautiful little girl Matilda was stillborn at 38 weeks. About 2 weeks after, our sister A announced she was 6 weeks pregnant and for the whole family, it was a very bitter sweet time as you can imagine.
The announcement was a shock for 2 reasons: A is in a bisexual but in a gay relationship and her and her girlfriend have been together a couple of years. Her girlfriend is adamant and always has been that she doesn’t want children.
B was bloody heroic throughout and managed to react excitedly on our WhatsApp when A talked about baby stuff and supported her when A was complaining how bad morning sickness was etc.
A was spectacularly tactless to the point that in the end I called A and explained while I knew how excited she was, she needed to tone it down in the group chat and maybe just message me without B in the chat if there’s things she’s excited about since A would be hurting despite putting on a really brave face.
A went ballistic at me and accused me of jealousy 
then stopped talking to me but continued to message B with giddy excited pregnancy chat 
None of us live near each other but we meet up fairly regularly normally. A hasn’t come to any of our meet ups since announcing the pregnancy because she says she doesn’t want to be around me and doesn’t want ‘her bump’ to upset B. Fair enough.
Anyway fast forward to now: I ran in to A’s girlfriend completely by chance on Saturday at an event and did the usual big hello hugs and fuss. I mentioned in passing how excited she must be for the impending arrival and how A must be getting quite big now, but she had NO IDEA what I was talking about.
I don’t know why, but I’d suspected something wasn’t quite right by what A had said before she blocked me so GF’s confusion kind of just confirmed what I already knew. I told GF that A had told us she was pregnant and GF confirmed this was catagorically not true. They live together so I can’t imagine she’d not know.
Anyway, 2 days later A unblocked me and had a WhatsApp rant about me ‘sticking my nose in’. Meanwhile I’d told B what had happened and she confirmed she also suspected the pregnancy wasn’t real.
I haven’t yet responded to the Facebook rant and A during her rant hasn’t confirmed or denied that the pregnancy is fake.
I want to cut her off and not respond but B is keen to understand exactly what’s gone on and why. We haven’t fallen out over it, but we’ve had major disagreements on how to proceed.
WIBU to just cut off A and not engage with the crazy and encourage my sister to do the same, or should we be trying to u defat and what’s actually going on?
I’m 100% sure there is no pregnancy.