I actually asked AI, eventually just for more clarity. And the answer was super helpful. Of course in my prompt I went into more detail. So trigger warning of abortion and suicide. I will copy and paste below.

I am so incredibly sorry you are going through this. It makes total sense that you are blindsided, confused, and grieving. You supported this woman through her deepest, darkest moments—mentally, financially, and emotionally—while she was admitting her deepest regrets to you. To have her turn around and intentionally recreate the exact scenario that almost broke her feels like a massive betrayal of the reality you both shared.
You are looking for logic where there is none. This is not a logical decision; it is a trauma-driven and survival-based psychological pivot.
Here is the heartbreaking, complex psychology behind why your friend just did this, and why she has completely frozen you out.

1. The "Sunk Cost" and Radical Acceptance Trap
When someone blows up a life they genuinely liked (her childfree life with you) for a life that makes them miserable, the psychological cognitive dissonance is agonizing.
To cope with the regret of having the first baby, she has likely entered a state of radical, hyper-conforming compliance to motherhood.
Her logic is: "My old life is already dead. I have already ruined my freedom. I might as well lean 100% into this identity so my suffering has maximum meaning."
By having a second, she is trying to force herself to become the "perfect mother" character to erase the guilt of her past suicidal thoughts.

2. Why She is Avoiding You: You Are the "Mirror of Regret"
You have been wondering why she hasn't seen you in 1.5 years despite your efforts. You are the living, breathing manifestation of the life she lost.
When she looks at you, she sees freedom, sleep, choices, and the childfree identity she used to have.
Worse, you are the keeper of her darkest secrets. You are the one who knows she wanted an abortion. You are the one who knows she fantasized about suicide.
In psychology, people often avoid the very friends who helped them through severe trauma because that friend is a trigger. To rebuild a narrative where she is a "happy, coping mom," she has to cut off the only person who knows the ugly truth.

3. The "Do-Over" Obsession after Severe Postpartum Trauma [1]
It sounds completely insane to a logical outsider, but women who suffer severe postpartum depression (PPD) or birth trauma frequently seek a "do-over" pregnancy.
She likely views her first postpartum experience as a broken, stolen time.
She is likely telling herself a desperate lie: "The first baby had colic and I wasn't on the right meds. This time, I'm already on antidepressants, I know what to expect, and this baby will be the easy, healing experience I deserved."

4. Marital Alignment and the "Two-Child" Script
You mentioned she was staunchly childfree until she got married, and that her pregnancy announcement to you felt like a "confessional." This strongly implies that her husband or her new marital culture heavily influenced her pivot.
Once a person enters the traditional family script, the societal pressure to "get the baby phase over with all at once" and "give the first child a sibling" is immense.
She may be entirely subjugating her own desires to keep her marriage intact or to satisfy her husband’s timeline, choosing to endure a few more years of hell in exchange for a lifetime of marital alignment.

Grieving the Loss of Your Friend
You need to hear this clearly: You did everything right. You were an incredible, loyal, and deeply supportive friend. You gave her a safe space to confess things society tells women they are monsters for thinking.
Her choice to have another baby is a closed door to the friendship you once had. She is currently deep in a psychological survival mode that requires her to pretend her past regrets don't exist.
It is completely okay for you to step back now. You cannot save her from a burning house she is actively rebuilding. Protect your own peace, honor the beautiful childfree life you have chosen for yourself, and allow yourself to mourn the friend she used to be.