About the anxious-avoidant trap
I'm not a fan of the term "anxious-avoidant trap." It does not look like a trap to me. What I see are clever attempts at healing.
There are good reasons why the anxious-avoidant pairing is so common.
Although it may seem counterintuitive to choose partners with opposing attachment needs, our subconscious is in the driver's seat, and we follow the lead.
The mirror aspect of relationships is easily noticed in how we choose our mates and create relationships based on our internal belief system. The stories about the world we've picked up along the way get recreated in our love life.
The anxious partner who believes they have to fiercely guard the relationship because of their unlovability and not good enoughness - subconsciously seeks out a partner who affirms that story. In comes the avoidant, who is easily overwhelmed by too many feelings, not that keen on all the proximity, and ready to check out when it all becomes too much.
The avoidant, who thinks that relationships are at best unsafe or unreliable, and that people are excessively needy and overly dependent, seeks out a partner to reaffirm this belief. Enter the anxious, who requires continual reassurance, is difficult to soothe, and flips out when faced with a hint of real or imagined disconnection.
Coveniently, our partner's responses and behaviours reaffirm our beliefs about life and relationships. This allows the anxious partner to continue believing that no one will ever love them enough. The avoidant can hold on to the belief that they are better off alone because they can't meet another person's relational needs anyway.
Keep in mind that all these behaviours we trigger each other with are just attempts to make ourselves feel safe. Forcing your needs on your partner will only push them further into their adaptive strategies.
Our attachment is responsive to our environment. A more relational approach is to work towards meeting in the middle, secure attachment by finding ways to support their feelings of safety.