<human>: Can you give me a shortened version of the text?

My GF's mom heard my GF(f/16) and I(m/17) having sex in her house. We've been dating for a year and 3 months. Her mom texted my mom later that night and told my mom this:
  "I try to give (OP) and (OP's GF) some space but I would appreciate it if I didn't have to turn up the volume of my TV to keep myself from hearing them have sex in the next room. (OP) doesn't really seem to care and I'd like for you to talk to him because I'm not turning up the volume of my TV anymore. Sorry :("

Now I know this is really messed up and I shouldn't have done this in the first place but we are really not that loud. My GF has a rather large home. We are generally quite and did not think we could be heard at all. I assume she heard is while walking around towards her room. I know this is not an excuse, I just highly doubt it was as bad as my girlfriends mom made it out to be. 

Anyhow, now my mother thinks I'm an embarrassment and I'm facing some irrevocable consequences with my relationship between my girl's parents and I. 

My mom confronted me this morning and I didn't even know what to say. I literally just told her I'm really sorry and I don't know what else to say. Needless to say this is an awkward situation 

How can I help repair this relationship or at least control the damage besides refraining from sex in her house? I will be seeing her mom within the next few days and I'm not even sure what to say or if I should say anything.
<bot>: My GF's mom heard me and my girl having sex in her home. GF's mom tells my mom. My mom and GFs mom is disgusted with me. What should I do?