You should download your manual here -
https://www.fleetwoodrv.com/rv-owners-manuals. It is good to be informed.
Your MH has 30 amp service, not 20 amps. Like others have said, if you are plugged into your friends house then your MH has access to 15 amps at best. If there are other items that your friend has plugged into the 15 amp circuit that you are plugged into then you have less than 15 amps available. I’m willing to bet your boyfriend is going to install a 30 amp outlet to your friends existing service so your MH can have enough juice.
Look at your friends power panel and look for a circuit that isn’t used by her that much. I would try a garage outlet that has maybe a garage opener on it and not much more. If you are going all the way in the house to plug in your MH then you’re asking for trouble. Don’t plug into her kitchen. Look for an outlet on the outside of the house.
I plug into my daughter’s garage all the time and it is 15 amp service. I can run the tv, x-box, charge phone, run the fridge and my small coffee pot at the same time. I can’t run my space heater and coffee pot at the same time. I can’t run the coffee pot and microwave at the same time. Welcome to the RV life style where you need to make choices - if you want to stay warm run the space heater and no toys. If you want to play then add a layer of clothes.