There isn't anything after life, because life never ends. It just goes higher and higher. The soul is liberated from the body and returns closer to her source than ever before.
The Torah assumes this in its language many times -- describing Abraham's death, for example, as going to rest with his fathers and similar phrases. The Talmud discusses the experiences of several people who made the trip there and back. Classic Jewish works such as Maavor Yabok describe the process of entering the higher world of life as a reflection of the soul's experiences while within the body: If the soul has become entrenched in material pleasures, she experiences the pain of ripping herself away from them so that she can experience the infinitely higher pleasure of basking in G‑dly light. If she is soiled and injured by acts that sundered her from her true self while below, then she must be cleansed and healed.
On the other hand, the good deeds and wisdom she has gained on her mission below serve as a protection for her journey upwards. You want a real good spacesuit to make this trip.
The Zohar tells us that if it were not for the intercession of the pure souls above, our world could not endure for even a moment. Each of our lives is strongly impacted by the work of our ancestors in that other world. Grandma's still watching over you.
Why should souls basking in divine light above be at all concerned about what's happening in your mundane life below? Because, there they feel the truth that is so easy to overlook while down here: that this lowly, material world is the center-stage of G‑d's purpose in creating all that exists.
That is also why, at the final resolution, all souls will return to physical bodies in this world.