In laws,is it just me are?

when your in a very happy relationship and u think no-one could make you unhappy,your partners family causes so much **** for example telling lies on you and saying hurt mean things such as being jealous of the 1st grandchild,cause i have a child to a previous relationship which there is no contact.which is soooooo NOT TRUE cause there child is so cute and hes fab,look i could write a book on them,after a 4months and alot of row with his family and him they apoligied totally because of our wedding coming up,my partner did take my part all along but at the end of the day blood is thicker than water,his family has drained every bit of energy out of me now im thinking am i making the right decision getting married,me and my partner im sure will have many a row as a couples does without his family getting there bit in.i really love my partner but i dont think i can cope will his family....what do i do i have my child to think of too?...... please help me...