On Sunday, October 13, 2019 at 3:03:20 PM UTC-5, wrote:
It is only a merger, NOT a collision.

There will be essentially no actual star ( or anything else ) collisions.

This is due to the relatively miniscule size of stars compared to vast distances between them.

After a few billion years of gravitational interactions, things will have settled down to a single stable resulting galaxy.

See you were planning on living forever after all.