OAP friend trying to live off me

hi all I am a single mom of a teenager and I'm in my early 50,s I've known this lady for years and have just meet up with her last spring, she has fell out with her own children and suffers with depressions as she is 12 years my senior and has trouble with letters she receives through the post so I started to help her, I meet her in a café in our local village and we have a cuppa tea /coffee but then she started watching my every move waiting on corners to see where I was going when I told her I had to go somewhere it was as she didn't believe me so hung around I thought it a bit odd so just shrugged it off as being a lonely oap thing, anyways I invited her around for a tea and she now comes around every chance and staying till very late and when I tell her I'm tiered and off to bed she starts another conversation some times I'm trying to feed my brood and even when I tell her she pretends not to have herd me so I end up feeding her to she's even asking me to take her on holiday with me and says ill pay my own fares there and back but its my holiday home and now I find myself a prisoner with her constant visits how do I tell her that I'm not a free ticket to all her needs without hurting her feelings any advice please as its affecting my family as well as me.

First question: What is an oap?? I'm fairly new to the world of 140 characters or less, so would appreciate some clarification. Second question: have you tried having an honest converstaion with her, one on one? About your concerns and irritations with how she's disrespecting you, your family, and all "normal" social boundaries?

Hi an oap is old age pensioner and yes I have had conversation with her but she seems to not take any notice.

Yes I am setting those boundarys now I went out today with out her seen her today but just for cuppa so I think she may get the hint in the mean time I'm just enjoying my time with my brood thanks for the advice all