The beginning of acowar wants to portray tamlin as bad and stupid for believing feyre would or could love him, but it accidentally makes him the only one to not doubt her. Feyre has told everyone that she was abused, but alis says, no, I heard you were smiling in summer, so I won't believe you and doubt you were abused. Tamlin is criticised for believing feyre was abused despite having gained weight and looking healthier. And it is to me a disgusting implication that abuse is always outwardly visible, that the right and good characters doubt feyre's story of abuse, while only evil tamlin believes her unconditionally. Feyre even uses this idea of outward visibility by herself abusing tamlin (bc yes the provocation into a breakdown and then consciously choosing to get hurt to portray yourself as a victim is reactive abuse, feyre is following the darvo pattern). But bc she bears the physical appearance of abuse it must be her that's the victim, there can be nothing psychological going on.
It also fits with Rhysand's powers as a mind manipulator, his abuse never leaves physical marks and is invisible and therefore not real. It is a pretty harmful view on abuse imo, to only view it as physical manifestation, be it malnutrition or wounds. It is repeated over and over again: lucien is abused bc he is seen wounded even though we never see how it happened, nesta is healed bc she is eating again, tamlin only registers as hurt in the narrative once he is physically thinner and unkempt.
The book cannot conceive that nesta and feyre are in abusive relationships as long as they are eating well. This could be an interesting comment on these girls being thankful for incredibly psychologically isolating and controlling situations bc they were starving for so long, the simple fact of not suffering malnutrition is enough for them. But I know for sjm abuse is only men punching and not men sweet talking and keeping information from you and controlling your food, your body, your location, your sexual behaviour, etc etc.