Although the poem describes a very strong love between the poet and Annabel Lee, not many "happy incidents" are mentioned. The most I can find is:
lines 5-6: And this maiden she lived with no other thought / Than to love and be loved by me.
lines 9-10: we loved with a love that was more than love -- / I and my Annabel Lee
The love between the poet and Annabel Lee is quite strong, and apparently quite pure and spiritual. We can only guess if this love ever came to any physical expression, but we do not see anything of this type expressed clearly in the poem. There is no mention of a kiss, an embrace, or even a stroke of a hand. Not surprisingly for Edgar Allen Poe, the strongest expression of love comes in his agony of longing after Annabel's death:
And so, all the night-tide, I lie down by the side
Of my darling—my darling—my life and my bride,
In her sepulchre there by the sea,
In her tomb by the side of the sea.
Of course, the poem as a whole does not speak of happy incidents. After all, Annabel Lee is dead at the end of the poem and the speaker is left in mourning.
However, the poem does speak, in the beginning, of happy times. You can see this in the whole of the first two stanzas. They both talk about how the love between the narrator and Annabel Lee was so perfect that the angels in heaven were envious.
This also helps us describe their love. It seems like a very deep and genuine love. It made them happy and that is the most important thing that love can do for two people.