Fiscal conservatism is a subset of social conservatism. Society should constrain the freedom to harm innocents while maximising the freedom to reap the rewards of one's own acts. Then criminalising abortion makes conservative sense as does criminalising drug trafficking if and when it impacts children. I honestly don't know if I'm libertarian about drugs and adults, but, legal or not, taxes should not be used to mitigate the suffering of voluntary adult drug users; charity, sure.
Homosexuals are already free to marry in any spiritually valid sense, but society should not be forced by law to punish, reward or endorse that spiritual contract. I'd go further and remove legal context from all marriage until children are involved. If a husband and wife want to make business arrangements, then use the law of contract. Marriage is properly valued by the unforced admiration of others and one's own self-definition, not by laws.
Let me not to the marriage of true minds
Admit impediments. Love is not love
Which alters when it alteration finds..