Don't settle for those minimum wage junk jobs. Be picky about who you will work for. Pick a trainer or competitor who is serious, has the backing, and can get you to good places. Check out their operation and choose to work for a manager who runs a tight barn. Well kept. Clean grooms. Decent vehicles. Serviceable tack.
Yeah, if you work for a larger operation you will have some co-worker drama. Being around people causes that. But, the upside is that there are more people to spread the work around and if you or someone else can't make it, there are more to share the extra. Also, you get more exposure to more ways of handling horses and general barn skills.
Good luck and have fun.