College Makes me scared to Fail

Straight into it, college is draining the absolute FUCK outta me, mentally and financially. As a neurodivergent person who loved school growing up (the routine, some of the subjects), I didn't know what to go to college for but my interest in lab work peaked my interest so I'm giving it a try.

 So far with honest effort, I've been a C- student at best. However for some reason when it comes to taking classes in the summer, there's always online classes ONLY and I struggle without proper structure. I brought up this concern with my mentor and I don't think the my concerns sticked to her because her main concern is that if I don't take summer classes, it'll take longer to graduate (I have to take 1 class per mini-semester due to pace, so taking longer isn't even a concern for me anymore). 

This summer passing, I failed my online class with a D+ (has to be a C- or higher). Now, I have to find 1k for 1 FUCKING CLASS in order to be able to register for classes again. 

This isn't the first time I've had a setback like this and it's very demotivating. I really really want to finish school despite how hard it is but I don't know how to continue with no motivation. Any advice from former/current college kids?