Giant Days: Susan and McGraw, Ed Gemmell starting with Big Lindsey, then various other girls;
Esther and The Boy were already a couple in previous universe, then Esther hooked up with another;

Bouletcorp, semi-autobiographical, John and his fiance; various stories have couples, e.g. Kingdom Lost;

Burne Out 2022: Husband and wife;
Decharge Mentale: Husband and wife

Emma & Capucine, French 2017, English edition 2025: Husband and wife and other couples;

Glorious Summers 2015: husband and wife;

Gremillet Sisters: husband and wife (but divorced),

Gunnerkrigg Court, Jack and Jenny, first seen in 2014

Beauty by Kerascoet 2014: husband and wife;

Ces jours qui disparaissent by Timothé Le Boucher: various couples;

Older:
Octopus Pie 2007: Hanna and Sven; later around 2016 Hanna and Larry
Widdershins 2011: several couples;