If you are really lost and can't keep up, or you had a case of premature cybering and really do not feel like typing for 3 days to satisfy your female counterpart, just pretend you got bumped offline. That always works and at least she won't take it so personal. If it was a truly bad experience, do not feel pressured into ever having cybersex with this person again. When they ask for your email address, just give them the wrong one. I never got your message.
Nobody needs to suffer a really bad cyber twice.
Last but not least, remember that cybersex will not make you go blind, unless you keep all the lights out in the house while having it, watching the screen in the dark does make your eyes burn. Realize that you may be addicted if your real life partner walks by naked and you'd rather be typing with one hand and still trying to keep a steady rhythm going. Sex can be just as nice with a partner you know. And just for variety, when your right hand gets tired, try dating your left hand for something different.