Interstitial Series by Ann Somerville

Love triangles. Alien monsters. Planetary war. Just another day in space. Sebastien ven Hester, decorated war hero and captain of the sentient cargo ship Naurus, can face any danger—except his own feelings. Jason North, his pilot, finds out the hard way that Seb’s not ready for a relationship after his recent divorce. And Jatila Kan, their engineer, discovers her feelings for North aren’t returned—because her lover’s pining after another man... moreLove triangles. Alien monsters. Planetary war. Just another day in space. Sebastien ven Hester, decorated war hero and captain of the sentient cargo ship Naurus, can face any danger—except his own feelings. Jason North, his pilot, finds out the hard way that Seb’s not ready for a relationship after his recent divorce. And Jatila Kan, their engineer, discovers her feelings for North aren’t returned—because her lover’s pining after another man. Not the best situation for a crew starting a three-week run across the galaxy. But there are bigger terrors in space than their messy love triangle. A ruthless, horrifying enemy stands ready to test them to their physical and emotional limits. Failure means certain death not only to themselves and their passengers, but to the entire planetary alliance. less

A short interlude between 'Interstitial' and 'Impedimenta'. In a sun-drenched luxury resort, Seb and North recuperate, sort out a few issues, and move their relationship up a notch. Jati deals with her demons.

A sequel to "Interstitial" and "Synchronised". North and Seb are still fumbling towards happiness, but the baggage they both carry is holding them back. Still, a six month mission on a quiet backwater of a planet could be the making of them…but then Jati has to go and say the fatal words: ‘milk run’. She should know by now that nothing is ever that easy – and space is full of surprises.