Bullying is bullying, whether it is online or offline, done by children or adults. Just because someone is being bullied does not mean they should then turn around and bully back whether face to face or through profiles. It never ends that way. LL rarely if ever does anything in regards to a resident bullying another resident unless it somehow got taken out of SL and into RL or unless one of the people involved is one of the SL Elite that spends enough money in SL that even the LL Gods have to take notice. So, you are left with three viable options (may not like them but they are the most viable options available).
1. Just continue to mute and ignore any and all avatars that pop up to harass you (and remove the nastiness you wrote in your profile as well because that just keeps it going. The best revenge is to totally ignore them, it will drive them nuts), which is what 98% of us have to do.
2. Make an alt and do not put anything in that new avatars profile that was in your originals profile (that includes anything that even remotely looks like something your original would say or do, the same types/styles of photo's, showing your groups, joining the same groups, setting your picks to the same spot your other avatar saved theirs at, your style of writing, etc.) Yeah I have been through this before, it's probably obvious huh. lol
3. Leave Second Life (which should not be an option since that means the stalker wins, but if you truly cannot handle it and the other two options have failed or you just don't want to try them it's the last resort)