Does always Pisces girl has to be independent when she with Gemini guy?

Pisces will often have planets in Aquarius and/or Aries (the signs on either side). This is because Mercury is never more than 1 sign away from the Sun, and Venus is never more than 1.5 signs away. At any rate, the independence you often see in Pisces comes not from Sun in Pisces, but from other planets in Aquarius and/or Aries, both of which are very independent signs.

Now, a Pisces could have their Mercury & Venus in Pisces instead of in Aquarius and/or Aries, and these Pisces are much less likely to be independent (they could still have Moon, Mars, etc. in an independent sign).

But any independent Pisces will be independent, whether they are with a Gemini, a Scorpio, a Libra, a Capricorn, etc. It's they person that THEY are, not who they are with.