Why did Luann go ahead with marrying Tom!?!?

I’m curious to know other peoples opinions on why exactly Luann decided to go ahead with marrying Tom when there were so many red flags beforehand. In retrospect I’m aware the engagement coincided with the incident of her ‘borrowing’ money from her kids trust so maybe there was a financial incentive. But at the same time while Tom did have family wealth I don’t think he was particularly rich and she didn’t end up getting much in the divorce so not sure that makes sense. Similarly I don’t really buy the idea that they had some sort of open relationship situation - Luann was so adamant they didn’t and the fact they separated so soon in the wake of more cheating claims doesn’t tally with them being open. Also having recently rewatched season 8 when they get engaged I’m of the opinion that Luann was having some sort of mental breakdown as she’s displaying signs of mania and just really doesn’t seem in her right mind. Yet she seems back to normal in season 9 when they actually get married so it also doesn’t seem like she just crazily decided to ignore the issues and go through with the wedding.

I’m interested in any theories as to why she decided to go through with the wedding in spite of the many clear warning signs that it wasn’t going to work out with Tom.