This is a fragmant of President Lincoln´s speech of March 4th, 1865, during his second inaugural address, in which he  refers to the Civil War. Due to the tone of the message, is evident that President Lincoln wants to send a general message of reconciliation and peace. This is evidnet in the cited lines, in which he is trying to explain that after all, the outcome of the war couldn´t really be anticipated by any of the parties, particularly in the lenght and magnitude of the war.
 
        
             
        
        
        
B. Older animals are usually surly and ill-tempered.- That can be a sentence in itself as well as the second part. Accordingly it is unwise to attempt to pet a grown raccoon. All the semicolon is doing is combining two sentences to make them one.
        
             
        
        
        
A dysfunctional relationship is one where two people make an emotional contract and agree to meet each other's needs in what end up being self destructive ways
        
             
        
        
        
I believe it is a run-on sentence but i am not certain