Cancer in moon men please answer (+gemini sun)

Guy has a cancer moon, venus moon, gemini sun and gemini mars.

He has had an 8 year relationship with someone (he broke it off in the end but said he kinda felt bad about it/missed her) and then a long distance 1 year relationship (and she broke it off and he said he really loved her).

He was very hot and cold with me (i.e. would be obsessively texting me from the morning to midnight) some days and then a little less on other days and always inviting me out, etc. Then, I had to move place (after a month) and he visited but then things cooled off a bit (he was very busy with going abroad, moving home, work, etc. but he'd promise to contact me once it was all over.

Since he got back, I initiated and we spoke briefly via text. Then, nothing for 1 month (by which point, I though whatever we had was over). Then, he contacts me again saying he was coming to my town (for a job meeting) and could see me all afternoon and then, sudden last minute things came up and he cancelled and invited me for the week after but that time, I couldn't go. He said that was no problem and said we can probably meet another time.

Then, had a few text convos initiated by me but he always seemed very interested (i.e. sending me 2 or 3 texts consecutively if I did not reply, etc.) but he never initiated anymore.. but would text for 12 hours straight if I initiated... and he always implies he will see me soon and is very flirty.

His type: he is very sensitive inside but pretends to be rather rude and direct with everyone (a hard outer shell), obviously he's hurt from his previous ex and I notice that me and her look VERY similar and behave similar-ish too.. he said he finds it hard to get over people and seems to have a "once bitten, twice shy" approach - he always seems quite insecure with me and worries about the age gap (which is quite large) and that I'd leave if I got someone younger (he'd mention this all of the time)

He did say that maybe in 5 years or so time, our differences in age won't feel as extreme as they are now (21 and 30)! He definitely seems very interested, attached, attentive, insecure and shy when with me. Why does he keep backing away? Is he just not that interested in us, would rather wait for the ex or does like me but is simply too scared of being hurt?

I really cannot tell if:
he just likes the attention (ego boost) from knowing I'm interested but doesn't really feel the same way or
keeping a slot free as it were, for the ex or
likes me soo much that he's scared of being hurt again - especially considering the huge similarities between me and the ex..

he said he did not feel like he had closure on his ex as she never had a proper reason for ending it.

Any advice/comments very appreciated