Neptune trine Neptune transit stimulates your imagination to see if something greater lies ahead for you, more so in the spiritual sense. This can manifest as increased empathy, sympathy, and compassion for other people.
You are becoming more sensitive and may notice you are more affected by the upsetting things you see or read about that affect many people or the environment. This could lead to involvement in charities, human rights, or environmental causes.
You should feel more unity with your generation and probably humanity in general. But the subconscious connection between you and others with a similar Neptune placement is powerful. You may also form a special connection with people of any age with a planet conjunct with your natal Neptune.
Joining groups will give you the sense of connectedness you seek. This could be related to your renewed interest in religion or spirituality, which is common at age 55 with this transit. You will also likely have more profound dreams and psychic experiences and understand them like never before.