There are common developmental milestones that twins experience as adults no matter what type of attachment they share:

Separation, both emotional and physical, is more difficult than adult twins have imagined. Overcoming these painful and confusion emotional experiences takes time, understanding of the problem, and experience tolerating being on your own. Twins and their family and friends have to be patient with this transition. Frustration and dogmatic direction is never helpful in the long run.

All kinds of new relationships – romantic, career, and children – inspire, motivate, and confuse twins. Developing a new sensibility about non-twin relationships takes effort, time, and some hard knocks. Understanding the problem intellectually is not enough. Insight into what is appropriate to expect from others is a good start. Experiences with new people, no matter how trying, is critical.

Understanding the different psychological boundaries you establish with friends is a long and bumpy journey. Learning that friends are not as able to understand you as your twin does is learned through experience. Being able to actually evaluate the good and bad about new relationships is a useful tool to have.

Mind reading like you had with your twin is not found with other people. Bottom line: Non-twins won’t understand you like your twin does. And working hard to explain yourself is for the best in the long run. Developing close relationships to replace your twin intimacy will take time.

Your twin may want your life or you may think that your twin wants your life. You will have to learn that you and your twin are separate people and not interchangeable with one another. As ridiculous as this sounds, twins often feel like they should be interchangeable. Sharing as adults is not possible and will only lead to unhappiness and anger.

Adult twins will experience loneliness, which is inevitable and can lead to emotional confusion, depression, and being overwhelmed. Non-twins will not understand the depth of your loneliness, which will only gradually fade into the background as you make new friends and get engaged in life without your twin.

Defining adult identity as an individual is a long and curving road. You will face competition and hardships along the way. Support from your twin will not always be available, which is most likely for the best. Find a therapist or a good friend who will understand your pain and happiness. This is when the search for a twin replacement begins.

Defining adult twin identity is an important process, which means getting over wanting to feel like young twins who only have each other to care about. Mature twin identity is caring but also limited to the reality of the different lives that are shared from a distance. Being an adult twin means knowing you are a separate person.

Searching for twin replacements is important and tricky. Twins can be overly hopeful that a new twin replacement has been identified. Often what seems like it will work out in terms of closeness and intimacy does not last. But it is better to try, and learn from your mistakes.

Learning to respect your twin and not be critical of their decisions is extremely important. Twin estrangement is based on a lack of respect and understanding.