Rejection is a part of life, we all have times when rejection of a job, a date, or a social circle for example that may set us back a bit but with time there is often growth from the experience. Living in an environment where rejection  happens frequently the feeling of unacceptance can overtake ones confidence and self worth.
Being rejected cause a reaction to hang on tighter to whatever is rejecting us. The worry of losing someone or something is more powerful than accepting the fact that you are being rejected.
The toxic personality will use rejection as a manipulation to get those in their lives to hang on tighter. This draws attention back onto them and they feel more in control and secure in the relationship.

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