NBC News reports although May supported Remain, she has said:
There will be no attempts to remain inside the EU.Beyond that, we don't yet know how rapidly she will invoke the two year process by which a nation negotiates its way out of the European Union. Since Brexit will be the first time leaving has occurred, there is no "track record" of how that process will proceed.
Earlier today I read a column arguing the EU will be maximally punitive toward the UK in an attempt to dissuade other possible leavers. Assuming that was the only issue on their minds, it would be a logical tack for the EU mavens to follow.
Others have argued being mean to the UK will economically hurt the EU's leading nations as well as hurting the UK. Economic pain is no small disincentive to the EU's leading nations.