The Catalyst (Targon Tales)

Lieutenant Nova Whiteside, on an apparently routine assignment aboard an
interstellar transport, finds herself the target of an assassination
attempt. Her escape leaves her with no option but to rely on Seth, a
former lover, for help.
Unfortunately, she realizes that they are
now on opposite sides of an escalating war between the Commonwealth
Union of Planets and an increasingly dangerous rebel organization.
In
trying to find who is threatening her life, they discover a plot to
destroy a distant planet - a world inhabited by creatures that are the
key to Nova's survival - and a conspiracy that threatens the stability
of the Union Commonwealth.
Can Nova go beyond her strict military training to cooperate with people whom she is sworn to destroy?
Book One of the Targon Tales space opera