I can sympathize with the sentiments above, but this is not a problem of weddings in particular, but of this wedding due to the bride's mom.
Do not elope. It is bad.
I know it is not popular to say in the current day and time, but the wedding is not for the bride and groom. Presumably, you already know that you love each other. Is a wedding really going to change that? The important thing is making a committment, in front of the community of your friends and family to be a source of stability in your relationship.
The community, for their part, is consecrating your marriage through their presence at the wedding. This does not make them any less a pain in the ass, but it does make it so that you are not speaking words of committment into a vacuum. Does it mean you don't love her if you don't get married? No, but as harsh as it may seem it does mean that maybe your love isn't worth anything in a larger societal context. It's up to you to decide if that's important or not.
Your marriage is a contract and covenant not between two people, but between two people and those that will give them support in the future. Take back your wedding, make it your own. They should be witnesses, not participants. Part of being a married couple is being able to stand somewhat independently as a unit, and your first test may well be to tell these family members to kiss your married ass.