It's not a matter of "developing a case of" anxiety like you didn't have anxiety and now you do - anxiety doesn't manifest itself the same way all the time. Other life issues affect it (for example a loved one went to hospital for a while and caused more stress) as well as sometimes people can think they're up for something and then it isn't possible to complete.
(Also it's more like "they could initiate contact to buy something". You have no idea whether or not it was "no problem" to do so.)
...but if they knew they had anxiety and are likely to flake, why on earth deliberately set up a situation where they're going to flake? THat's, again, just plain inconsiderate. Why not at least say in the first message that they might not be able to get back to the other person (no need to specify reason) so if they don't hear from them in x days, feel free to sell to someone else. I mean, it's pretty clear that OP's contacts didn't do this, or they wouldn't have been left hanging like that.
Re: da
(Anonymous) 2016-02-24 08:56 am (UTC)(link)(Also it's more like "they could initiate contact to buy something". You have no idea whether or not it was "no problem" to do so.)
Re: da
(Anonymous) 2016-02-24 11:18 am (UTC)(link)