If a partner struggles to be emotionally available, it is often because they are protecting themselves from fear of rejection, fear of abandonment, or fear that they will be exposed as not being good enough for their partner. This often can come from past trauma, previously bad experiences in relationships, or low self-worth. I find that one of the most important processes and goals of couples therapy is to help both partners feel safe to be more open and honest about their feelings. This requires time and patience, as the individual must learn that vulnerability can be safe and beneficial.