alovelycupoftea....it's not clear what caused the problems are here, but if you've apologised, then I'd leave it at that.
All I would say, from my stepchildren's behaviour, with my late DH, is that halfway/bouncing estrangements can cause a huge amount of stress. I used to wish that they'd just cut us off totally. I seriously cannot deal with adults sulking around.
Sometimes, other relatives do still keep in touch - I'd just ask those relatives not to tell you anything. Not to mention any of it.
I'm sure what this lunch invitation is - if it's your son and DIL inviting you, and your daughter to lunch, then go if you want to go, and not if you don't, then go, with an open mind.
Do what makes you happy, and meantime, get on with your life - no one should hinge all their happiness on what adult children are doing.
Best wishes and welcome to this thread 💐
Terrible relationship with DIL - am I the problem?
So it begins….. Streeting resigns

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