Guest attire to a 1pm wedding and 6pm reception

I am going to a wedding the end of September and the wedding is at 1:30pm at a Catholic Church and the reception is at 6pm at a fancy golf club. I have been told that both places are pretty fancy. I am wondering if it is appropriate to wear the same dress to both events or if I need to get another one. My boyfriend is wearing a black suit with either a matching shirt the same color as my dress with a black tie or a white shirt with a tie to match my dress. Does he also need to wear two different things?
The dress I purchased and planned to wear is a floor length dress that is a chartreuse/green-yellow hue. It is polyester with an acetate lining and has a great soft look to it. The dress has a v neckline in the back and front that starts at the top with 1 1/2″ wide strap/material that goes into the main body of the dress. In the front it gathers with a gold pin and is form fitting. The back is gathered by the bottom to add detail and has a short chiffon detail coming off the back center seam line the rest of the way down with a slight tail to the main part of the dress. I consider the dress to be elegant. I was going to wear gold toned strappy shoes, dangly earings, a gold bracelet and no necklace. I am not sure if my age helps, but I am 23. I was planning to wear my curly hair up with some ringlets down. Should I wear my hair and makeup differently at the wedding and reception? I planned to be doing my hair and makeup myself. Thank you for all of your help in advance with my many questions – it is greatly appreciated!

Rebecca Black, Etiquette By Rebecca

Dear Guest,

I believe that your dress is too formal. Unless the invitation stated ‘Black Tie’ it is too formal. Even if it did, your dress would be too formal for the wedding.

I would imagine that cocktail attire would be best for both. You could wear the same outfit if the dress had a jacket. This would tone down the dress for the wedding. A nice suit would work too. You could wear a conservative top for the wedding and more festive one for the reception.

Your boyfriend doesn’t have to match you.

Best wishes,