Hello, welcome to the forum
I'll use the 1st house for him, and the 7th house for her, as you are not involved in the question as you asked just about him breaking up with her.
He is Saturn, she is Moon.
Moon has just trined Saturn, showing them together.
There is also mutual reception between them, showing a mutual interest too.
Moon is in the 1st house in Aqua, showing her being close to him, and he is welcoming her being her depositor. He also holds more of the cards in the relationship.
Looking to the 4th house from the relationship, I think this is the 10th house, Mars rules this and Moon squares this. This shows a 'no' answer to me.
If I also look to the natural 4th house, Venus, then Moon also squares this, another 'no' answer.
Did he show any signs that they may break up?
It is bad news for you, I'm sorry, but it looks like they are very much together.