A Friend at the Highland Court by Celeste Barclay

Alexander Armstrong, heir to the Clan Armstrong lairdship, took for granted his strength and size until that strength was taken from him. Injured during a skirmish with another Lowland clan, Alex finds himself struggling to wield his sword. His once handsome face is now marred by a vicious scar. Forced to attend court as his father’s representative, Alex’s anger and bitterness threaten to chase away the one woman who’s loved him most of her life.
Lady Caitlyn Kennedy usually finds the bright side of everything. Friends with Alex since childhood, when he fostered with her clan, Caitlyn attempts to lure Alex back from the brink of self-destruction. But their once budding romance seems destined to fail. Alex recognizes he’s losing the woman he’s loved since he was a boy by pushing away the one person who can heal his unseen wounds.
Can these friends-turned-enemies turn into lovers?