suggestions for my horse

Let her be around the trailer without trying to load her a few times before trying to load her again. Like just lead her around it with the ramp down but don't go too close to the ramp so she knows she's not being loaded and theres nothing to be scared of.
Be very patient and if it has back and front ramps have them both down so there is as much light in there as possible so she doesn't feel trapped.
Don't force her on. Encourage her that its safe, but don't get in to a tug of war with her or she will just resist even more.
Give her plenty of praise when she steps closer to it even if its just one step.

Those are just some fairly basic ideas, but they may well help. Most of all remember to be paitent and not to get frustrated or mad at her, cause she'll know you're tense and get more tense herself. I went with the yard owner I used to help to get a new horse once and it took us an hour and a half to get him loaded, he reared and trying to run away and broke the trailer in the process. But on their last attept to load him they had basically given up hope of getting him on and wern't really being as determind as they had been, and he came as far up as having all feet on the ramp and his nose at the entrance and I jumped up there with him and coaxed him the rest of the way with food. He came cause he wasn't being forced.