Talia, Do not beat yourself up at all for feeling this way!! It is COMPLETELY normal...and I think it's better to expect that there will be some natural comparison for quite awhile. It will diminish over time, but will still be there for awhile. That's OK. I think it might be weird if it wasn't.
For me my first real date was about 8 months after H left. Initially I was kind of giddy and so happy that I could have that feeling of 'spark' back with someone. But it was more of a fling/physical thing than any potential for future relationship. 2nd/3rd dates with same person I started to like the guy a bit more...but then realized he was a bit of a player/a*hole and that's when - as soon as I returned home the next day - I had a meltdown. I missed tenderness and deeper closeness of H (beyond the empty hook-up) and it really came crashing down. The partnership and good qualities from the past I missed. But along with that an acceptance I kept/keep working on of, THAT MAN (my H) no longer exists in the way he was before. There is no way on but forward, and part of that process is dating a few frogs, or even a few great guys who you will still compare H too.
Honestly, in the broader scheme of things given the time you've been with H and the fact that this was a M (not a simple relationship breakup) 6 months is still quite early. Be patient with yourself. Be kind to yourself. And know that's it's all part of the normal transition.
A great GF said to me weekend after fling-boy fizzled and I was bummed was: think of this in stages. First stage is go out on a date/hook up with a guy. Check-you've accomplished that. Second stage is going on a date with a guy you really like, and then date 2 and 3...and see where it goes. It's a process and you're not likely to be with/see any future potential right away, with the 1st (or even 2nd or 3rd) guy you go out with post-H.
If it feels funny/weird/sends you reeling for a bit..it's ok to take a break for a bit then. After my first fling (or whatever you want to call it), I went back to doing my processing/healing for couple more months and then have just rececently started getting back out there again.. Out with friends, flirting have fun, not with the expectation to meet a guy but open to it if it does happen.
Remember (and I like to this of it this way) it is a PARALLEL PROCESS: the letting go and moving on that is. You may 'move on' to date, but you are still 'letting go' and they happen together so be gentle with yourself if one seems farther along that the other...or you back track for a bit. Sometimes it's 2 or 3 steps forward, and then 1 or 2 back. That's OK.
I think you did great by being open to it, but also know that it is early for you still, I think. Do what feels right. Don't beat yourself up (you know I do that at times too!)
Awesome you had great convo though and let's you know that YES - you can connect with another guy! And there will be many others you will be able to connect with in a deeper way if it's not H. You're getting your energy in the right place.