Remember your voice is part of your body and therefore, part of yourself.I grew up in Spain, watching dubbed films and television series. This caused me quite a lot of confusion sometimes and often took the joy out of watching t.v. Still does. In the 80s, the dubbing industry was a closed shop. So there were a handful of voices dubbing a whole range of in-the-flesh screen presences. To this day, sometimes I watch a dubbed series and think: "That voice, that voice...Furilo!" (By which I mean that she is dubbed by the same actress who dubbed Captain Furillo's wife in 'Hill Street Blues'.)
Voices change very little as you get older - unless you change drastically yourself. Unless you change your behaviour; or your physicality either out of choice (to fit in) or not through choice (for example, as a result of an illness). Next time you speak to someone on the phone who you know quite well, notice how quickly you can pick up their mood, their energy, their propensity to have a conversation with you. Wholly focused on their voice, it is easier to sense how they are feeling.
The voice rarely lies, which is why sometimes theatre directors and acting teachers will stop watching a scene and just listen, to hear whether what they're listening rings true.
Changing your voice is as difficult or as easy as changing your personality. We all adapt our voice and behaviour to the situation we are in and who we are with. The more relaxed we are, the more we let our true selves emerge. And, as with every part of our true selves, we are more accepting of some aspects of our voice than others.