Oh boy I have been there before. I was 3/4 of the way through a 175,000-word novel when I decided it needed to be first-person instead of third-person. I liked it a lot more after the rewrite, but I went through all five stages of grief before I got there.
A lot of the time I would try to write things in third-person first because so many people say they find first-person annoying or childish. But I have now accepted that I just prefer writing from a first-person perspective. If someone doesn't like first-person narratives, they're just not my audience, and that's fine. There are plenty of great works of literature written in first-person.
Of course, now I've started writing something in third-person, and while I'm pretty confident that's the right decision for this story, if I get halfway through it and decide I need to switch again, so help me god...
I'm glad switching perspectives made your writing experience better! Sounds like it was the right choice.