Proving that if the odd and even sequences converge, where one is decreasing and the other is increasing, then they converge to the same limit

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I'm trying to prove this statement for this sequence as a part of a larger proof. The specific sequence I'm looking at is : $b_{n+1} = 1+\dfrac{1}{b_n}$, where $b_1 = 2$. I'm attempting to show that ($b_{2n}) \rightarrow A \land (b_{2n-1}) \rightarrow B \implies A=B$. I know that this statement is not true in all cases, e.g. if $b_n = (-1)^n$. For this reason, I think I might have to use the fact that for this specific sequenence, $(b_{2n})$ is monotonic increasing and $(b_{2n-1})$ is monotonic decreasing. Note that I am not assuming that $(b_n)$ converges from the start, and I am not trying to show that it converges to the same value as the subsequences. Is the statement: "if the odd and even sequences converge, where one is decreasing and the other is increasing, then they converge to the same limit" even true in general? If so, how do I go about proving it? I'm completely stuck on how to proceed with the information that I seem to have.