A strange new start

Hi everyone. My name is Meg, I'm 27 and this is my first post here. So here it goes.
I was broken up with in November from my boyfriend of 5 years while we were traveling abroad. He was working, I wasn't, so I had to leave (I will post about this in due time ;)). I left England and went to Germany where I was previously working to see what I could accomplish before heading back home to Greece.
While I was there, a friend contacted me and said he would be in the same city I was in on a business trip and we should meet up. I knew him through my ex, we used to hang out now and then with his ex girlfriend. Now about him, he's 38 and he was in a relationship with her for 8 years and they lived together for about 4-5. She eventually fell in love with someone else and he had to move out (this was around August 2012 I think).
We ended up hooking up and having a wonderful time while he was there, kept in touch after he left, saw each other a lot during the holidays when I went back home and talked every day when I went back. Ultimately, I had to come back home to Greece in January since I couldn't find a job in Germany.
Ever since I got back though, it seems he's more "cautious" around me. We don't go out much (he does work long hours though), but when we do he's not as expressive as he was during the holidays (a lot more PDA then). I haven't met his friends yet and vice versa. We're generally pretty low key (mostly hang out at his place) although he would tell me when I was gone that we would do all kinds of things when I got back. He does seem interested to keep seeing me, but I just feel like now that I'm back for good, he's taken a step back from how it all started.
We do have a really good time though; we talk, listen to music, watch movies (very similar taste in all these) and he does occasionally ask me to spend the night. The sex is amazing and he's very giving in that area.
I do think I am reading too much into this, being suspicious from being dumped and afraid of rejection again and I know he's for sure more cautious from his breakup scenario as well.
I just have this insecure feeling that something isn't "right". I really like him, he's a good guy.
The more I read what I've written, the more ridiculous it seems (thought about not posting at all), but I'd still like to hear opinions.
Thanks for the read :)

If your gut is telling that something isn't right, then it's probably correct. Can you be more specific about him having taken a 'step back' from how it used to be?

Had s hard time following who went to what country etc but I think I got the gist... You two live within reasonable driving distance of each other I assume?

He may just be taking the relationship more for granted. Before when you two were countries apart, he felt he had to make the most of your time together. Now he might just be like, "OK fine, she will be around".
Things in any relationship do fizzle down after a time. Worst case scenario - think of how married couples sometimes just see their spouse as just "kind of there".
In your case, it does not mean there is something wrong or that he wants to dump you. I would not worry too much unless the dates and visits start getting spaced further apart like it used to be weekly, then every two weeks, then a month, then God knows when...

@basilandthyme: He was more enthusiastic, now he's more in a "relaxed and let's see how it goes" kind of phase.
@AnErin: Haha yeah the country situation was a bit complex, but yes now we live 15 mins apart. The thing is we've only been dating for two months now, how can it have started to fizzle already? But no, the dates aren't drawing apart and even though we don't see each other every day, we do make an effort to at least speak on the phone daily.
I do agree, since I'm more available, maybe it's just become a more relaxed situation, probably reading too much into it all :)
Thank you!