You think this 'star counting' trick is astrological

When my mom was younger she was sitting on her porch with some lady. She out of nowhere asks "I wonder how you know who you're ever going to get married with?" this women told her that counting 9 stars starting on any random Thursday and ending the Friday of the next week. So counting 9 stars every night before you fall asleep starting a Thursday and that Friday night after that week, you're supposed to dream of the person you're going to get married with. My mom dreamed of someone calling my dads name and she dd meet him like 10 years later. Have you ever heard of this? What is it? Like some sort of witchcraft thing?... Also, my mother heard this from a small town women so I'm just saying cuz usually small town people believe in all of these things and are very superstitious. What do you think?

It's a superstition, like the May Day dewdrops, cakes under the pillow and so on.

However, like many superstitions, there is a hint of truth in it. In this one, the 'hint of truth' is that, if you think about what you want in life, and want it strongly enough, then it will 'manifest' itself in some way. It doesn't matter what your want is, but the whole works.

In most small towns, girls believe that marriage is the most important thing in their lives, so they really look for ways of getting married. Getting into the habit of counting 9 stars every night from a specific day is just a way of concentrating your mind on what you want. If it's marriage, then it will happen. Of course, it is very likely going to happen anyway, but so what? It's the thought that counts!

And what has this to do with astronomy and space?

I think that the only line of evidence to support this hypothesis is anecdotal. For that matter, your one "hit" here, presuming her anecdote is accurate, might well have married the person BECAUSE she had the dream.