Dating a 25 year old
She went to high school and lived with her parents.
Since then almost 4 years past and we live together in another city and we are both happy and in love.
That way you don't force her to change her life, yet still make her aware of the concerns.
Several answers already, but I want to address a couple of your concerns.
Since the first time I feel like she is the perfect match for me and she thinks also like that.
I was afraid in the beginning that this age difference could be a problem, but it's not.
The general rule of thumb for age appropriateness is half plus 7.
I know its only 8 years difference but it's the difference between him being at an age where he must be thinking about starting a family, marriage, etc and her starting out in life. Do I let them get on with it or should I try to explain my above concerns at the risk of pushing them together?
I think the most important thing to do is not push your daughter away with any shouting matches or 'you are doing the wrong thing' this is what my mother did and although she was doing her best in a difficult situation - the shouting and threats simply pushed me away further.