Overall, Is It Worth It?

I have started reading Melissa's book and had built up so much hope just because she is totally describing my relationship.  It has made me feel like I am not crazy for wanting to stay in it - we are engaged, and I said yes because I *want* to marry him, I *want* to build a life together, but I still have doubts. Then I came to this forum and reading all these posts has me so despondent.  Is it worth all the work?  I stayed in my first marriage through years of his alcoholism because I believed in the commitment and I thought we could eventually work it out.  Then he left me to marry one of our best friends - yes I know, very cliche.  Now, I live with someone who, well, all of you have described quite thoroughly....so another cliche?  Don't read my other post because I obviously shared too much too soon thinking this was different than it actually is.  Can an engineer who thrives on her life and home being organized really make a marriage work with someone who self-describes as "ADHD AF" and thinks "clean" means most of the dishes are in the dishwasher but the rest are piled in the sink and the counters and floors have not been cleaned (just as an example)?  I was planning to register for the couple's seminar - is it worth the time and investment?

As you consider answering, please know that I am happy with my fiancee 80% of the time.  The other 20% is driven by mess, disorganization, and finances.  And I do love him so much and can't imagine life without him.