Hi Nadalie,Linda says in Relationship Signs that one´s Sun opposed the other´s Venus is surprisingly a good vibration for love and marriage, assuming that one of you controls a tendency toward extravagance and the other controls a tendency towards false pride.
There´s a great deal of affection between you even when this is a stressful aspect. Because the Sun and Venus are such benefic planets, no contact between them is seriously antagonistic or dangerous to a relationship. However, with the opposition there may be some accusations from one partner to the other of extravagance or stinginess, and perhaps frequent disputes over money.
Differences in cultural background may cause some friction. Also different lifestyles with confronting interests may lead to minor disagreements. There could be marked differences in taste, again a minor matter, whether in the area of home decor, clothing or entertainment.
As for the cutural background differences, both people should learn from the other.