Marriage just depends on astrology is blind to believe. Marriage depends on two persons love. No hindu scriptures has written that one should always marry by checking kundali only. Even if it is written it is not a neutral note.

Does Jupiter give love marriage?

Jupiter represents spirituality, Honesty, ethical behavior, morality and acceptance of Social norms. So a regressive or weak Jupiter also helps in Love Marriage. When planet Jupiter connects with the combination of 5th and 7th lord, it will be a marriage full of love.