Could you please explain these lines to me?

Since her passions were almost never returned, she kept her illusions.

...does it mean that since her emotions/passions were almost always one-sided and there was hardly any response from the other end, she started living in her own world of imaginations.

Many thanks for your time,

Mr. Tom she started living in her own world of imaginations.
I think you're going too far. I don't think "having/keeping" an illusion is necessarily "living" in it. Emotion: shake

(Of course prior context may shed a different light on it.)

What's the significance of your title, BTW??
I've changed the title.

I agree with the general sense here - because she didn't have a chance to have an actual relationship, her illusions about these people and her fantasies of what their romance would have been could remain.
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Without any more context or background, I would say that your interpretation makes sense.

she started living in her own world of imaginations. "Imagination" in this context is uncountable, so it should not have an "s." It woud only take a plural if you were talking about more than one person. (For instance, "They have very vivid imaginations.")
 Avangi's reply was promoted to an answer.
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My sincere thanks to both of you.

My title is simply a typo--and by the time I noticed it, it's too late. Could you please change it to:

"Explanation required: She started living in her own..."

 BarbaraPA's reply was promoted to an answer.