Wasn´t her father so thrilled that she married a Royal?
Actually, Albert was reluctant to allow the marriage on account of Astrid's age. She met Lorenz at her 18th birthday ball and fell head over heels in love and wanted to marry right away. Albert refused to consider a marriage until she was at least 21, so as soon as she turned 21 she got married.
Lorenz is considerably older than she is.
Uncle Baudouin was the one who was reportedly thrilled that she was bucking the trend and marrying into such an ancient Royal House as the Habsburgs.