I would give your instructor a call and tell her that while you are still hoping to get back to her lessons you are going to be looking for another instructor in the interim to keep up with your riding. There's nothing wrong with it, and the potential for conflicting ideas will hurt you much less than not riding while she gets her stuff sorted out.
THAT is one thing about the horse world that frustrates me to no end. I completely understand that sometimes life happens and you need to put things on hold. What I don't appreciate is when people can't do a 30 second phone call to say "Sorry, I'm having some family issues at the moment. I will not be able to give lessons in the meantime, but X will. I'll let you know when I'll be available again. I'm really sorry I have to cut our conversation short, but I have some errands that I need to attend to". It really isn't that hard to keep someone in the loop, and I've had these problems with instructors, shippers, and numerous farriers. I don't blame anyone for having problems in their life, but being polite and explaining the situation goes a long way towards keeping clients.
I would be willing to bet that if you give her a call and mention taking lessons elsewhere (even temporarily) that you'll get a call back tomorrow to tell you what's up. This is YOUR riding career, not hers. You don't need to wait on the sidelines until she gets back with you when there are other riding options out there. I'd tell her first and see if she straightens up, and if not find somewhere else. You can always go back to your original trainer if she finds herself available again... but you may find you like the new place better. When I was young I started riding with the barn owner at my barn. She ended up running out of lesson time, so put her younger, less experienced, and what she thought were "less serious" students with the new trainer. Time passed, and I kept with it. Bought my own horse, and was paying the new trainer for lessons and training on him all through high school. She did get money for my horse for board during that time, but told me once that she regretted passing me on to the new trainer when I was young.