The likeness is excellent and you capture her mysterious quality very well! Its unmistakably her and I know shell love it for that very reason. Her pose is quite deliberate as is her aesthetic sense of what she wants to portray to the world. Youve done her justice and that takes talent.
Talent is not something you can acquire. You can only develop your artistic skills which allows your talent to show through. Your oil painting chops are as good as any long timers, so if youre just starting to use oils I cant wait to see how you develop ease of using it.
By the way, all artists who are true to that inner calling that compels them to go deeply inward to bring some elusive thing into manifestation on a canvas will struggle. Its the essence of artistic expression.
Technically you have shown the ability to use your tools to render what your eye sees. The details of color, texture of her hair, smoothness of her skin and shiny brilliance of her lipstick and the amazing details of her eye are amazing. Your portrait depicts her as a very bold woman, with a direct, almost defiant look taking the viewer by surprise even as she obscures her face with her hair. You show that in this pose she has two contrasting aspects. One side shows her showing us who she is in a bold, direct way, with that half of her hair shaved and her strong, unwavering and almost defiant stare, while the other side is shrouded, completely hidden from us, not allowing any detail to show. The overall result is that this is a portrait of a real and complicated person who feels quite comfortable in her persona.