Advice needed please

[Nanakitkat]

Hi guys I’ll try and keep it short but I’m really struggling and need some input.
Basically my friend left her two boys with their dad many years ago. Age 5 and 7. She walked away and had no contact for 15 yrs. fast forward her eldest needed a kidney they tracked her down. A very strained relationship evolved which has now broken down again due to her own stupidity . Her youngest has had another child she found out on Facebook and is in bits that he didn’t let her know.
Here’s my dilemma, whilst I’m trying to be supportive I really struggle with the fact she left her kids. She is now refusing to see her step grandchildren and will not visit me when my grandson is staying as “it hurts to much”. Not to bothered about me but her husband is pulling his hair out, and has had to explain to his son that she won’t be visiting the 3 grandkids. I just can’t get my head around it? She is hurting lots of people with her actions. It feels like she’s punishing us because she can’t have a decent relationship with her estranged kids. I’m trying to understand but I seriously feel like I’m banging my head against a wall and I’m walking on egg shells with her as I can’t even talk about my GS in case she gets upset! I’m seriously at the point of dropping our friendship to save my sanity 😳

[Nanakitkat]

Just realised as a first time poster that this is probably in the wrong place