We have to cover the cathedral's costs, although these are negligible considering the alternatives! Further donations are voluntary though. I'm told there will be a collection from guests after the ceremony, which I'm sure will be very lucrative with 80+ guests. My SO also attends mass so is expected to tithe (admittedly I always seem to forget my wallet when I get dragged along

). I think they manage to balance the books somehow...
April update:
After reading YMOYL I have taken a renewed interest in analysis of my financial data. I previously used YNAB to record my expenses though decided that its reporting features were too restrictive. I use excel in work for performance reporting so have decided to try my hand at tracking my finances in it too. The YNAB data collected through 2014 was limited in terms of details. I didn't break down my spending into any specifics, i.e. groceries into staples vs discretionary purchases, alcohol etc, so I'm starting a fresh as of March, luckily the net worth data I have is still useful, although nothing to shout about!
You might notice I started to get serious about my financial situation about June last year, although progress was painfully slow due to various financial commitments which thankfully all ended recently. I ditched the car in February this year and discovered ERE just a few weeks before... I haven't witnessed the full benefit of following my new financial philosophy yet, however my expenses have been unusually high these last two months due to extraordinary/unplanned expenses, despite this my net worth has moved up not down! Now I have no debts I should be able to see some quick progress in my net worth over the next few months.
You will notice I am tracking two values for net worth, the first is the total net worth figure, including my workplace pension, although this cannot be accessed until traditional retirement age >55, therefore I have excluded this from my second line, 'ERE Net Worth' which will be my preferred gauge of progress. In order to reach FI I'll need >£200,000 in liquid assets. I admit, there are a few other assets that I haven't bothered to list which I may add in the future, though for the time being I'll only be tracking liquid/cash assets.
I have also included a summary of expenses for April, these were quite high compared to my budget for the month. However I'm really pleased I managed to bring my food bill down from £300 to £237, despite high spending on alcohol. The budget feeds myself, my SO and the dog (leftovers). Spending on alcohol, restaurants, drinking in bars, taxis and giving is much higher than I would normally allow, but it was my SOs birthday and her close friend's wedding that ruined me this month, despite this I managed a savings rate of 52% in April. When sticking with my budget, I should be achieving
72% savings rate. Spending on books was also significant this month, however I am stocking up for a two week break in Greece next month. Obviously, these are mostly from the ERE reading list (bought used of course!)
My SO told me today she has been thinking about homesteading, this isn't something I expected her to dream about in all honesty, but seems like my endless ranting about self-sufficiency is sinking in! I haven't sold her on the idea of keeping pigs and chickens, but there's time. I'm extremely excited and upbeat about the future. This month is my first opportunity to see my 75% savings rate finally come to fruition. Fingers crossed.