hmmm maybe
assumption:
date is stored in standard mysql format of YYYY-MM-DD
$year = substr($row_gethistory['date'] ,0,4);
$month = substr($row_gethistory['date'] ,5,2);
$day = substr($row_gethistory['date'] ,8);
$newMonth = (($month+2) mod 12) + 1;
if($newMonth < $month) {$year++;}
$test = strtotime("$newMonth-1-$year");
if(date("t",$test) < $day) {
$newMonth++;
$day = ($day - date("t",$test));
}
$finished = strtotime("$newMonth-$day-$year");