Coworkers want for children turning uncomfortable

My coworker is in her early 40’s and going through a divorce.

She has mentioned before that she wants kids. Which there are still options in your early 40’s.

But her and her soon to be ex husband decided they weren’t in a good financial place to have children, so didn’t.

Her brother recently had a child and she is obsessed with her nephew which is great as she can bond with him and be super close.

Fast forward a few months and a 30 year old coworker became pregnant and things got weird. The coworker in her early 40’s is making it very uncomfortable for everyone.

Making comments like “I’ll just pretend I’m you” or “must be nice” or “I’ll buy you outfits that I think pregnant ladies can wear”. She cries at her desk whenever the pregnant coworker is at a doctors appointment.

Then her brother wife got pregnant again and she freaking lost it. Meltdowns everyday. Unfortunately, her brothers wife had a miscarriage.

Then she went back to her weird comments and told the pregnant coworker “youre all I have now”

She is obviously hurting and going through something. And I am sad that she is struggling. But it is so uncomfortable in the office with all of her comments and breakdowns! I want to suggest she get some help but idk how to do it respectfully.

We are a small business and I am technically her boss and we don’t have a formal HR department. So I can’t just send it off to HR.