Alliances and friendship are orthogonal. An alliance is a pragmatic short-term matter. Friendship is something more fundamental and typically lasts longer.
Germany and the USSR were almost allies during the early years of WW2. The Soviets supplied Germany with massive amounts of raw materials, helping them to circumvent the British blockade. There were even serious talks on the USSR formally joining the Axis powers. The talks ultimately failed, as Germany and the USSR could not agree on their spheres of influence in the south.
Then the war between Germany and the USSR broke out, and Cold War followed after the war. All these changes happened in less than a decade.
Germany and the USSR were almost allies during the early years of WW2. The Soviets supplied Germany with massive amounts of raw materials, helping them to circumvent the British blockade. There were even serious talks on the USSR formally joining the Axis powers. The talks ultimately failed, as Germany and the USSR could not agree on their spheres of influence in the south.
Then the war between Germany and the USSR broke out, and Cold War followed after the war. All these changes happened in less than a decade.