My country bought the F-35 for the sole purpose of being a deterrent to a future Russian invasion. Now that the US and Russia are allies, how can we trust that

My country bought the F-35 for the sole purpose of being a deterrent to a future Russian invasion. Now that the US and Russia are allies, how can we trust that those planes will receive spare parts and other support during a conflict? I think European alternatives for F35 are obviously needed.