when friend become an enemy

gutten morgen, peoples.
how's the day? mine? not so bad.... hehe :3
today, the enemy's making me wanna share this post. yah, she/he already break my mood for this morning. when first, we're close friends. we talk each others, sharing so much fun and laugh, also sadness together. then, he turn into something that I don't know. just... BUM! and everything changed. and when he turns into something good again, what should I do? blaming myself because can't keep the friendship well, uh? sorry I can. it's too much problem. GAHHHH, frenemy, just go away. please.