How do you build emotional intimacy?
Emotional intimacy requires vulnerability. Most people struggle to show vulnerability early on in any kind of relationship - especially if they've experienced intense emotional pain in relationships before.
You can try to lower the threshold for your partner through creating emotional safety. You can focus on showing unconditional acceptance (non-judgementality), genuineness and understanding (empathy) through your own behaviour. Also try not to put any pressure on your partner to open up more. This can push your partner further away. You can further build safety through your own emotional transparency - but try to be careful to not be drastically more transparent than your partner, as this may be threatening.