“He compares me to his ex”

What could be going on

Triangulation: Fits if the comparisons make you compete and keep you insecure.

Devaluation: Check whether comparisons come with putting you down.

Grief (complicated, disenfranchised, anticipatory): He may still be processing the loss; check whether he talks about her sadly rather than to hurt you.

Idealisation: The ex may be idealised in memory; check whether he forgets the problems.

Idealises, then devalues: Check whether he once idealised you too and has turned to devaluing.

Social comparison: Could be habitual comparing that he does everywhere, not targeted at you.

Also said as

• my boyfriend always talks about how his ex did things
• she keeps saying her ex was better at stuff
• why does my husband bring up his ex wife
• he still praises his ex in front of me
• my partner compares me to his ex girlfriend
• my wife keeps mentioning her ex husband