Hmmmm....I found myself getting a little annoyed wheile reading your post and for that I apologise. I dont know you, and so dont want to judge you but I was in a simular position.
I am married to my hubby almost 11 years now and when we met were both in really good, well paid jobs, went on several holidays a year, regular new cars and didnt have to watch money really at all. Before we got married, he started his own business, which was paying a wage but less then before (so I was earning more then him) and then he proposed. I was of course delighted and didnt consider at any time that the business might not be successful as times were good. The business expanded, he took out loans etc and the business continued to do well, although paying him a wage less then before but we were happy and managing fine
Slowly, things started to go a little quiet...then quieter but like you say, limp along! Then we got married
However, the business eventually suffered from massive tax and insurance hikes and the decision to shut it down was made. although none of the loans etc were in my name, I saw it that WE were liable for all the debts and it took us years to clear them all...but we did it! I never thought well, you started that business before we got married so the debts are all yours mate!
I guess what I am saying is, even though we had business debts coming out of our ears I didnt at any stage consider NOT marrying him...you marry for better for worse, for richer for poorer!!
I do urge you to really think about what you want (forget about the money) and then really discuss it with your DP.