Your suggestion would work well on a wide screen but maybe not so well on a phone?

How about using one column/table.
Each event in a box/container with different coloured margins for followers and following events.
Then different colours for the text to separate follows, unfollows and mutes.

The final column/table to have the following in chronological order:

Followers follows (when another user follows you) - green margin around yellow text
Followers unfollows (when another user unfollows you) - green margin around purple text
Followers mutes (when another user mutes you) - green margin around orange text
Following follows (when you follow another user) - red margin around yellow text
Following unfollows (when you unfollow another user) - red margin around purple text
Following mutes (when you mute another user) - red margin around orange text

https://en.wikipedia.org/wiki/Complementary_colors

The end result risks being too much colour but might allow for speedy analysis.