Keep in mind that everyone's motivations can be complex and unique, so these are only educated guesses:
Ego Boost: Bragging about seeing other women and emphasizing that he won't choose you could be an attempt to boost his own ego. He might be trying to make himself feel desired or in control by showing that he has other options.
Seeking a Reaction: Your ex might be trying to provoke a reaction from you. By mentioning his interactions with other women and his lack of interest in a relationship with you, he might be hoping to elicit jealousy or a desire to win him back.
Maintaining Control: By stating that he won't settle and only wants a sexual relationship, he may be trying to assert dominance or control in the situation. This behavior could be an attempt to keep you emotionally invested in him without committing to a relationship.
Insecurity: Bragging about other women and sexual relationships might be a way for him to mask feelings of insecurity or fear of rejection. By putting up a front of confidence, he might be trying to protect himself from potential emotional vulnerability.
Moving on: It's possible that your ex is genuinely trying to move on from the past relationship and is doing so in an awkward or insensitive manner. Talking about seeing other people might be his way of signaling that he is trying to explore new connections.
Regardless of his motives, it's essential to prioritize your own emotional well-being. If you've made it clear that you don't want to date him and his behavior is causing you distress, it's best to distance yourself from the situation. Consider setting clear boundaries and limiting contact if necessary to protect yourself from any emotional manipulation or hurt. Surround yourself with supportive friends and family to help you through this challenging time.