receiving sms in my email?

I am not sure how this is happening or why... I randomly get my text messages sent to my email inbox instead of my phone. Sometime it won't happen for a few days, then some days it will do it a whole bunch of times, BUT it only happens with one particular person who is also a verizon user. I'm not sure if it is settings on his phone, or mine, or with one or both of our accounts, but does anyone know how to make this stop?

we both use verizon wireless online, and the email address it says it comes from is his login name at vzwtext dot com, not from his phone number.

?????

 

its from from phone to phone and phone# to phone# just like a normal text - no computer or email addresses involved. he isn't sending these any different from any other text he sends me.
it just so happens that it goes to my email for whatever reason.

 

we don't know if it is happening to anyone else he texts, but it could be. it doesn't happen to me when anyone else at all texts me, just him. i haven't had any other problems with anyone elses texts or any other carriers.

 

he doesn't have my email in his phone so that can't be it, and i could say for him to test other verizon users but it is so random - it won't do it for a week and then all of a sudden do it for a whole day long. the only thing i can think of is it might be if my inbox is full sometimes... is there anyway for it to auto delete the messages at the bottom of the box?

 

so i tested the inbox full theory over the weekend. i kept my inbox less than half full and it still did it... once on saturday and three times on sunday. i can't figure this out and it is really annoying! i will try to put on the auto erase feature, which i had previously thought would auto erase them right after theyhad been read (not saving any messages), which is why i didn't turn it on before. we will see. thanks for all your help.