My ex is asking me to try again

We were 20 years old and studied together. We were inseparable; everyone said we were going to end up married.
When I graduated, I went back to the university to look for her… and there she was. Several months pregnant, walking down the hall. She saw me. She just looked me in the eyes… and smiled. A calm smile, as if nothing was wrong.
I didn't say a word. I turned around and left. I blocked everything and disappeared from her life.
More than eight years passed. I never found anyone who made me feel the same way. Relationships that lasted months and then ended. I felt broken.
A few weeks ago, I was at my lowest point: I had just lost my job, I was alone in my apartment, and everything was falling apart. I went for a walk to clear my head… and suddenly I saw her crossing the street.
She recognized me instantly too. She came over, we were silent for a while, and then she said:
— 'Life didn't turn out the way I planned. I raised my son alone all these years… but I never stopped thinking about you. Can we try again? I know it's a lot to ask… but I miss you.'
I froze. She was still beautiful, but now with the look of someone who had lived too long. She didn't mention the child's father, nor did she apologize for that smile from years ago.