Jethabel. Leviathan, #1

Book 1 of the Leviathan series. Captain David Arman is worried. The fleet is falling back (again) and leaving Sheraton port to the hands of the Tren armada. Arman is staring at the worst rout any member of his family has faced. Worse than Aunt Andrea's capture at Endimon, which has been the talking point at every family event since. To salvage his reputation he needs to go down fighting, but his orders are to take as many refugees as will fit on board and run.
Jayleigh Printer has charge of a science program with great potential for the war effort, but he too is abandoning Sheraton with whatever he can carry and as many test subjects as he can keep hold of. It's imperative that he gets his charges safely back to a home-world, but that's not easy with Tren deep cover agents on his trail. Between the two of them and the Tren, first officer Greg Hawthorne finds himself questioning his loyalties and struggling to stay alive.