Tradition says that couples may not touch before marriage. One who follows that is called shomer negiah.
Yet when Jacob met Rachel he kissed her:
וַיִּשַּׁ֥ק יַעֲקֹ֖ב לְרָחֵ֑ל וַיִּשָּׂ֥א אֶת־קֹל֖וֹ וַיֵּֽבְךְּ׃ -- Then Jacob kissed Rachel, and broke into tears. [Genesis 29:11]
Sure, the Torah had not been given, but tradition says that the patriarchs followed the Torah before it was given. (As for marrying two sisters, later forbidden, Leah and Rachel were converts, which severed their biological links).
Resolution?