I think its hard not to take repeated rejection (especially when you never get any kind of 'reason') personally. Its something I have struggled with. I fully accept there will be instances where there is simply no spark, I think most people recognise those when they happen, but it's the dates that go well, if not brilliantly, after which you never hear from them, or you do and then contact tails off for no reason, which leave you thinking 'wtf was that about?!'
I have realised through several years of OD crap though that most men who are on sites don't want a relationship. They are either looking for an occasional hook-up (and once you sleep with them you'll never see them again, or if they don't get anywhere in the first couple of dates they'll move on to someone else) or else have such an idealised image of the woman they want no-one could possibly measure up.
Hence why the majority of first or second dates never get beyond that, because you're simply not on the same page. Most men who OD aren't nice, genuine, guys unfortunately. The nice ones out there are in the tiny minority and take some finding!
I rarely assume any bloke I encounter via OD is looking for a relationship, until proved otherwise. Similarly I don't trust much they say. Or place any store in how well we get on, how good a time we have together, or whether there seems to be chemistry, because so many men BS over this stuff that none of that is any indicator of whether it will go beyond date 1, 2 etc.
I do find it depressing having to be so cynical and negative about it all, it's not in my nature!