According to Dreamcrowd:

To see your boyfriend in your dream, represents your waking relationship with him and how you feel about him. To dream that your boyfriend is dead, indicates that something in your own Self that is no longer functional and is “dead”. You are not being allowed to fully express yourself. It is also symbolic of your own relationship with that person. Perhaps you need to let go of this relationship. If your boyfriend is away and your dreams of him involve a lot of touching, signify how much you miss his presence and have him being nearby. The dream is telling you not to take the day to day things for granted. Learn to cherish the smaller things in life. To dream that your boyfriend tells you that he is gay or that he doesn’t love your anymore, represents your own insecurities with the relationship. It may also mean that the relationship is moving to a new level to which you are expressing some anxiety and fears about the changing situation. You may feel left out it in his life or that you are unable to share in all his experiences. It boils down to trust and communication.

Try posting your dream on Dreamcrowd for a free interpretation.

Wedding Dress
To wear a wedding dress in your dream, indicates that you are evaluating and assessing your personal relationship.

Marrige
To dream that you are getting married to your ex, suggests that you have accepted aspects of that relationship and learned from those past mistakes. Alternatively, it means that a current relationship shares some commonality with your previous relationship with your ex. However, you will not make those same mistakes.

Ex
To dream about your ex-boyfriend/girlfriend or that you and your ex got back together again, suggests that something or someone in your current life that is bringing out similar feelings you felt during the relationship with your ex. The dream may be a way of alerting you to the same or similar behavior in a current relationship. What you learn from that previous relationship may need to be applied to the present one so that you do no repeat the same mistake. Alternatively, past lovers often highlight the positive experiences you had with that person.It could also signify aspects of yourself that you have x’d out or neglected.

it could be related to the above or
maybe you still have some feelings for him, maybe wondering what could of happened if you went on or related thoughts. Your mind could of been just clearing up.
if you do like your ex boyfriend even by just a little or still trying to get over it. the dream could aslo mean your trying to get rid of these feelings but your not completely getting through with that (“While we were hugging i felt the dress(at the bust) was falling off”)

hope this helped.

you probably on the topic of being happy before you fell asleep.the only person a husband figure you thought at the dream was your ex. so possibly you wanted to marry but he is what you thought of.

here are a few sites you can interpret dreams…

you must still love your ex try to get back with him

To me this dream says that your really have feelings for this guy. Marrying your best friend can go two ways. It can either make the most wonderful marriage, or it can destroy a friendship. It appears you have some unresolved feelings about giving him up. Is he still available? Does he feel the same or has he moved on? You can check it out and see where it takes you, or just let it be. Good luck in either choice.

Hmmmm I WONDER!!! MAYBE U STILL LOVE UR EX!!! its possible isnt it?