Is it normal i miss my crush from last year sometimes

Sometimes I miss my most recent crush which is an older man I met last year. We were both interns at this store because we were longterm unemployed at the time (we are both employed nowadays). There was quite the age difference seeing as he was 40 at the time and I was 25 but when I first saw him I fell for him immadiately but it was from a bit of a distance and I thought he was late 20s/early 30s because he looked young and had a young demeanor with small frame if that makes sense.
It was me who started paying him attention first. When I first said hi to him he looked very surprised. I dont think he was used to female attention which made things very fun for me. Then one day he asked me if im coming to lunch and it was very cute. He was open with me about himself. He confided in me he got diagnosed with aspergers a few years ago and have struggled lots with depression. This was relatable for me who also got diagnosed with aspergers a few years ago. We also liked the same stuff.
He started to always stop by and speak to me whenever he saw me and I caught him looking at me a few times when he believed I would not notice. I was very into him. I've never had such a natural connection to another person so it's very unfair we couldn't be the same age. I felt my social anxiety leave my body when he approached me and I started acting in a way I did not recognzie about myself and felt confident and fun.
On his last day he made a comment about it being good to be in the same age range as somebody. I'm not sure why he in bypass said that to me and it felt a bit hurtful like he found me juvenile. He later in the same day stopped by me when I was working and said it's been great knowing me but maybe we will see each other again and that he might come by the store on weekends. I havent seen him since though which was in March but I didnt go there on the weekends until a few months after my internship was over because I didnt want to chat with my coworkers. I dont know why I miss him its not like there was anything special about him but it's that connection I got with him. I would've tried to stay in touch via social media but he doesn't seem to use social media and anyway there would be no point. I mentioned him to my mother once when talking about work and she didnt like it one bit that we talked at lunch. I am not a person who can handle anything complicated. It's just a memory now and will remain so.