The first thing I would recommend is to start from language acquisition, not from a textbook. A textbook is a shot in the feet. Language acquisition works only if you are immersed in a language environment every day. Start from watching your favorite TV shows in Russian. When you acquire enough language, you will have a strong feeling that you need to talk to somebody in Russian. Second, find a language partner. Only than start learning formal grammar. And last, the significant lack of motivation is maybe a signal to you that Russian is simply not your thing. If your family language is Russian you would have known the language by now. So it is.

Hi Vivien! To have a motivation it's important to have a certain goal like "I want to see Russia with my own eyes" or "I want to speak Russian with my family". To learn a language for somebody it's a bad idea as it demotivates but when you do it for yourself it changes everything.

motivation of learning a language like a fall in love - there be or not if that is gone, maybe it would be better to take something else? (in my humble opinion) ^^^

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