Toddler HATES HATES car seat!! Help!

We have an issue we are struggling with. Our DD is 3.5 years old and hates being in her car seat. On good days she will happily jump in it and get buckled in, which basically really makes our day, and rarely happens anymore. I would say it’s becoming one in three times she will start flipping out when trying to get her buckled in. Everything from her avoiding her car seat to throwing a huge tantrum just trying to get her in. During those days it can take upwards of 20+ minutes just to get her buckled in. My wife and I are about to give up because everyday is a struggle with this and we are at the breaking point.Things we have tried that are working less and less:Bribing. It used to work but has become less effective over time. Putting a towel in her car seat as extra cushion. This is hit or miss and she seems to be fighting this more often. Saying she’s a big girl and letting her buckle herself in. Which works sometimes. Threatening liberties and toys being taken away. It’s like she doesn’t care.I mean, she’s complaining about everything to stall her being buckled in. She says her diaper is hurting her. We have straight up taken it off and let her ride in nothing but pants or shorts, and even then she still complains about something.She has always been anti-car seat and it was a struggle since day 1, and everyone kept saying “oh it gets better! One day she’ll jump in it and buckle herself in.” Its been years of this non stop struggle each. And. Every. Day. To the point where we need to start heading out the door a half hour early so we are not late. Also, she does this in parking lots after we go shopping. A trunk full of groceries just sitting there and here we are 15-20+ minutes of trying to bribe and convince and sometimes threatening to take toys and liberties away just to get her in her fu***** car seat! It’s so damn exhausting!We’ve been considering just putting her in her booster seats already, despite her being nearly 5lbs away from this mark because right now, it’s just getting to that point that we are cracking. Any help or advice on this?? via /r/Parenting http://bit.ly/2Rmroqt