Wow, again I got a chill down my spine. No boundaries was what I experienced too. My stalker would get kicked out of his basement room every so often because he sat around the house all day and didn't contribute and was volatile. He begged me to take him in and I almost did. That would have been a disaster. Like you, my stalker was always trying to change me to fit his regressive views of women and he would have done the same to my house. You're right, who would do that without permission or even some discussion...or at all in someone else's home.
I empathize with you on being easily fooled. My friends say I'm way too trusting. I give far too many chances when everyone else tells me to give up on someone. I once had a coworker who consumed 90% of my time and energy because he was lazy and incompetent and everyone told me so from the beginning. You're right, finding good friends who give and receive is important. I was blessed by having friends who supported me through this stalker. I totally agree too on feeling like you had invested so much to just let the person self destruct. My stalker and I were actually good friends for six months prior and I still do care about his well being. On rare occasion I see the old him in his texts and videos and I'm tempted to respond, but I know better and within an hour, his roller coaster mood swings kick in and he's cursing my name.
While I hate to say misery loves company, I am glad to commiserate with someone who understands how dysfunctional this all is. I hope you have a great day.