From before ... Taking a break

The guy I had dated for about half a year suggested us taking a break
from our sexual activity.  Why would a guy decide not to have sexual
activity with someone he's seeing and still want to remain friends?

I still want him in the interim even though I had always been unsure
about him as a long-term potential.  I am in love with him.
Subsequent to our break, I reached out to him several times where he
responded sparingly.  I told him that I would like to continue seeing
him, even if it meant having a casual relationship.  We weren't that
serious to begin with anyways.  Recently, not too long after our
break, he texted that he definitely still wanted to see me, but felt
like we needed a "cool down" and would reach out to me later.

What does that even mean?
Do guys usually end casual relationships when the other person
involved gets too emotionally attached?

This is the long version:

 I started dating  a guy over six months ago, and several months into
it, we both agreed that   even though I've never really casually dated
before.  Throughout the six months, I wasn't sure if I wanted to be
with him and expressed many anxious thoughts to him (i.e. not sure
where this is heading, not sure if we're compatible since he's so
different from any guy I've ever dated, unhappy about his
communication style, and so forth).

I like daily communication (either via texting, phone, email, skype,
etc).  He communicates with people only when necessary and will only
reach out like once a week.  He also hates talking on the phone but,
in the beginning, he made a real effort and talked to me a handful of
times.  The texts were more frequent as well until it started
dwindling (from pretty much daily to one every three-four days to no
answers).  He exhibited all the signs of a man in love, and I truly
believe he felt something strong for me.

I acknowledge that I probably drove him away by my uncertainty about
him and stupid comparisons between him and my past boyfriend.  But I
couldn't help it.  He's much older than me (10+ years) , with a lot
more life and love experience, with an unstable income, and a much
more liberal attitude when it comes to dating.

I could envision him as a great father and possibly a great husband,
but his current financial situation precludes those options.  Yet ...
I couldn't end things with him even though I didn't see him in my
future.  It was just so hard to contain my feelings, especially since
our physical chemistry was out-of-this-world.  And typically I'm not a
person driven by my hormones, but in this case, he had many other
redeeming qualities that made me go back to him.

I had wanted to end things with him several times.  When we finally
decided to take a break, he basically was the one who suggested a cool
down, a break from our sexual activity.  He said he was tired of not
meeting my expectations and hurting my feelings (since I am accustomed
to daily communication).  He also said that he was looking for a
destressing relationship, one without any expectations since he had
other areas in his life that were stressful and still needed to be
accomplished.

My initial reaction was both sadness and relief - sadness because I
love him and there's a little part of me that wants to work it out
with him.  Relief because I no longer had to torment myself about
whether or not I should continue seeing him.

Ultimately, despite all my practical reasons of "why the break was
good for me," I still want him back.  I was devastated and though I
have resumed my normal life and started dating again, he is constantly
on my mind.

After we discussed taking a break, I reached out to him and basically
told him I was willing to work it out, even if it meant pursuing a
even more casual relationship.  I told him I'd be willing to adjust my
expectations and work with him.  He didn't respond.

The other day he finally responded and said he definitely would still
like to see me, but he just felt that we needed a "cool down" and that
he would reach out to me.  I asked him what that meant, but he didn't
give me an explanation.

So I reached out to him over the weekend asking him if he wanted to
meet up,  but he didn't respond.  Now I am officially confused.

Why is he saying that he still wants to see me, but not responding at
all or reaching out to me?  Why would he decide to take a break in the
first place when we were just seeing each other casually?

I admit that perhaps he was afraid that I was too attached and getting
to the point of wanting more, but I wasn't.  Do guys usually end
casual relationships when the other person involved gets too
emotionally attached?