You are the Moon, in Sag in the 5th, of casual dating.
He is Saturn, in Aquarius, in your 7th, but his turned first.
At first he was thinking of you, as shown by the sextile between you and him. But that is an aspect from the past. It is now separating.
A couple other aspects have happened for you since then---The Moon sextiled Jupiter---did you have another potential opportunity that diverted your attention?
The Moon trined Chiron---A good chance that you made some spiritual or emotional progress in your healing journey?
However your ex has an applying conjunction with Mercury in Aquarius in his 1st. Does he maybe have a new friend? Mercury rules his turned 6th and 9th---maybe a coworker or student?