Severely avoidant people tend to miss their toxic exes more while forgetting about a relationships they had with a healthy ex. This is because toxic relationships create highs and lows, which stimulates the severely avoidant person. Whereas a healthy relationship creates less stimulation. Therefore, when a severely avoidant person is feeling disgust about a low moment with a toxic ex, they will also feel nostalgia about a high moment with that same ex.
This is why severely avoidant people are more likely to rekindle a relationship with a toxic ex than they are with a healthy ex.
In addition, a toxic ex is also more likely to prolong the drama so they are willing to rekindle a relationship. Whereas a healthy ex recognizes that the relationship was not good for them and will have moved on to a new relationship that is stable and healthy.