No-one can really tell you if your being walked over. We dont sit their all day
next to you like supernanny and tell you where your going wrong. You have to
work that out for yourself.
Genuinly, I used to say yes all the time when asked to do something for someone,
but, now i can tell the difference between a "David, can you help me? I'm really
stuck on this part of something" and a "David, can you help me? I really cant be
****ed to do this and want someone else to do it for me" If their genuinly
stuck, i try and help out, make it easier for THEM to do the work like break it up
or whatnot. I dont do the work for them, tell them what it is I done and they
take the credit. One way to find out is to say no to them and see what they say
or do. From their reaction / answer / tone of voice etc you should be able to
work out if they are walking over you or genuinly need the help. Thats what i
did.
As for the GF it seems to be a normaly girl to me (well, in comparison to
mates GF's and sisters and general girl mates) Although, again, you can try
and say no to a request of hers and check body language / tone of voice blah blah blah and work it out.
And I personaly think asking for advice on a large forum is a good thing! You
got thousands of people on here. some may be able to help, some might not
but if you dont ask, you wont know.