Wiktionary
lose oneself in
vb. (context idiomatic transitive English) to be deeply occupied, focused or absorbed in someone or something
Usage examples of "lose oneself in".
If one does not get lost on the way one is bound to lose oneself in these towns, and to avoid them is impossible on account of their size.
It is a world so inspiring of awe that one can lose oneself in it, for one man seems so insignificant.
He felt that it was more dignified to lose oneself in business, as he intended to do, than in alcohol, as Tom was probably doing.
It is easy to lose oneself in the crowd waiting for the train, and slip away.
Abundant places to lose oneself in, if one were determined, and Marie was that.