I have experienced this same thing. I have dated two different men after my divorce (I wasn't even looking, one I meet in Meetup and one I was lined up) and both times they got serious after just a few dates, of course my walls went up and I went the complete opposite direction. While I was open with both men about my feelings for my divorce (unwanted) and still being in love with my ex, they both backed off and gave me my space, but it didn't help and I just kept pulling away and was so uncomfortable in dating. The first one just quit texting and it didn't bother me enough to find out why. I'm ok with that one. I had deep feelings for the second man and I tried to make it work but I just couldn't let go of the past so he and I talked and broke up. I miss him, I care for him but I'm not in a healthy dating place right now and I don't want to hurt him at all, so I'm not going to date him or anyone right now.

While I am lonely and miss the attention of a man, I'm concentrating on my family and day to day life. I still need to get out of my home and find a new place to live. I will be putting dating on hold for awhile.

If you're ready to date, might as well keep trying!!! Good luck.

it depends upon how things are defined,

i am a man, just starting stating to date post marriage,
i'm on a dating site
i'm upfont about what i'm looking for
(looking to date ~ 3 to ~ 4 times, and then if we like each other,
then agree to be exclusive
exclusive at that point only means, no "noise" from others,
as we date more to see how dialed we want to be

to me, exclusivity at that point, does not obligate nor imply anything is serious

and since it is a site in which you are in contact with each other,
it is easy to put that out there, before you meet each other

Thanks for the comments - at least I know I am not alone. :-)