A frustrating problem with my cable internet plz read

[Nick999]

I live in a small town composed of around 2500 people. We have one cable company and a telephone company. The telephone company offers internet through dial-up or DSL, and the cable company offers cable internet which is provided by CableRocket ISP that i believe is in Belvielle, KS. Well ive had my cable internet for a very long time now, with no problems, but last winter the telephone company bought the cable company and shortly after i noticed a decline in my internet speed which is 384kbps. Soon after a couple of months it got so bad i was barely able to surf the web and doing so required hours of loading not to mention i couldnt even come close to playing games. So i called the telphone company and complained, they said to call CableRocket Tech support, and so i did. They told me they noticed a "Low threshold" from my connection and dispatched someone to take a look at it for me. Well no one came, and the reason why is because when i called customer service (Which is the telephone company) they said they cancelled the dispatch because my connection slow down was do to THEM rate limiting it to 56kbps. I was like what!? they told me i was using too much bandwidth and killing their network. Which raised a question in the fact that i never had this problem when they didnt own the cable company but now i do. And i dont seriously think they have the right to limit my connection from an ISP im paying. Should i call up CableRocket and tell them about this, or is my Telephone company in full rite to rate limit my connection like this?