Every relationship has peaks and valleys.
The initial meeting, the spark of meeting someone who you find incredible and, hopefully, feels the same way about you, that sends you flying into the stratosphere.
After the initial joy wears off, then you see the flaws, and you expose your own to them, and that can lead to disaster.
But, if you both stick to it, you can ride that out, and rise again to the top of the mountain once more in the bliss of a full, loving relationship.
Then go down again, into the valley of dull monotony.