Those babies whose mothers are not emotionally (or physically) available don't "turn on" a portion of their brains, the right prefrontal orbital cortex, because they don't have consistent interaction with mother or primary caregiver during the first year of life. This leads to attachment problems.
There are reasons why we mothers act the way we do. We jump whenever baby makes a "peep". We talk in that screechy "gootchy, gootchy, goo" voice known as "motherese". We're programmed that way. Baby's brain "rents" our brains to help "jump start" their own neurological development. It's a really big deal. So, if mother is ill (mentally or physically) or baby is ill and unavailable to mother, there can be lifelong consequences.
I refer to the right prefrontal orbital cortex as "the seat of humanity". This part of the brain contributes to the emotional give-and-take necessary for healthy relationships. It also allows us to "relate" to others, have empathy and be able to predict "what's next" in an exchange or emotional event. See where I'm going with this?
Parents and teachers spend a great deal of time teaching children how to get along with others. They teach the rules of relationships and insights about how others are feeling as well as offering suggestions getting along with others.
The focus of our conversation is primarily about having a parenting partner who has attachment issues and the burden it brings to you as the other parenting adult and to the child. Clearly, if your parenting partner is unable to respond empathically and consistently to your children, it falls on you to "pick up the slack".
1. Secure/autonomous: This is the healthiest style and suggests a strong "start" to life with competent parents who are emotional educators. These adults value relationships; they do not idealize or feel angry about their childhood. They integrate the positive and negative experiences of childhood. They know that everything can't be sunshine and roses and understand their own parents' limitations. They have securely attached kids of their own.
3. Preoccupied: These adults are confused/incoherent regarding attachment memories. They childhoods are characterized by disappointment and role reversals (acting like parents and parents are dependent on them). They are frustrated in their attempts to please their parents. They stay enmeshed with their original family's issues, are angry and have a sense of resignation that their problems cannot be overcome. Most of their children have ambivalent (anxious/resistant) attachment.
4. Unresolved: This impaired adult attachment profile is the result of severe trauma and early losses. They have not mourned or integrated their losses. They are frightened by memories of trauma and may dissociate to avoid the pain. They have negative and dysfunctional relationships with their kids and are often abusive and neglectful. Their children have a disorganized/disoriented attachment profile.
Clearly, I'm not giving you this information so you can diagnose your partner. However, if you have questions, making observations and understanding the nature of their family will help guide you in getting the support you need. There are several YouTube videos of Peter Fonagy discussing adult attachment that are worthwhile.
Consult with a psychologist specializing in adult attachment issues. Understand that even if your partner does not go to therapy, it will be invaluable to you. I believe in playing the game with "whomever takes the field"
You will learn not to take their emotional challenges personally. You will develop reasonable expectations not only for your relationship, but the relationship they have with your children. You will learn ways to minimize the impact of their attachment problems on your children's ultimate emotional adjustment to adulthood. It will be an education. You will learn ways to gently pierce their "emotional armor".
Don't deprive yourself of support. Understanding the "why" behind the "what" will break the cycle of unhealthy attachment.
Just do your best.