Yes, confusingly.
In the present day, Abby Conroy is Mason's wife, and they have a child and house together in Wyoming. Both met at an amnesiac therapy group.
The fact that both these memory-wiped individuals is a lucky coincidence because they were also spies at the same time for Citadel, and Celeste is the name that this woman went under then. She didn't have a romantic relationship with Kane, and in fact they were hostile to one another.
Brielle is the name that Abby/Celeste went by during one important case, when she infiltrated the Silje brothers and their weapon-making scheme. So in the present day, lots of characters know her by that name too.