Love / Why should I support my partners sister and boyfriend? [23]

Ok So let me introduce myself I am a 30 year old English guy I have been seeing a polish girl for almost 2 years now, we are having our first baby in march, I met my partner through a mutual friend, and we have lived together since after 2 weeks we met.

My partner was working in a food factory, she is from a small village near Warsaw, her sister decided she wanted to come to UK also so we arranged for this to happen, I paid out of my own pocket over £100 to set them up with a new mattress and new bedding, they rented a room from our other mutual polish friends who live a few streets away from us, my partner knows these friends from Poland as they live in the same village also. They wanted to rent from these friends with a view to live together with me and my partner in a bigger house than I have now in a few months time, I found out my partners sisters boyfriend only wanted to use us so he can also have his sister come to live in UK also. Once his sister would arrive in Feb they were going to leave us in a bigger house with bigger bills and rent, basically they only care about his sister coming to UK and not about my new forthcoming family.

So my partners sister arrived along with her boyfriend, they rented a room from our friends for £90 a week inc all bills which was fine as they were earning almost £200 each when they both were working in the factory, and even if only one was working it was £190 a week, this was in August and they stayed renting this room until Christmas, so a good 4 months, they found out the factory will be closing at Christmas and they did not want to pay £90 per week for 3 weeks with no work so they flew back to Poland, and asked my girlfriend if they can stay with us until they got a place themselves. Anyway January and they came back to UK this time to our place, I was not happy as we live in a small 1 bedroom flat on top of an old man and other old neighbours, I am supposed to live alone and if I got reported with 4 adults coming in and out I would probably be evicted. My neighbours are old and nosey lol! My girlfriend assured me they will only stay 2 weeks.

anyway 2 weeks have gone past they are staying with us free of charge and are totally using us, neighbours already know they are staying with us so its dangerous, I didn't even agree for them to stay with us as its not even convienient, they are living in our front room! I am in my bedroom everyday and its stupid, I found myself calling around agencies and I finally got them a place a house to rent 3 bedrooms for £395 a month. I had to as they were not doing much at all to get a place, and they were trying to stay here free until mid Feb they were hellbent on getting a particular flat in Feb so they can save money here until then. I wasn't having it as I have a baby to think about and we cant save when they are here with us. Anyway now it finally looks like they are moving I provided a reference for them on this 3 bedroom house answered the call said they are great tenants, they have the keys to move now. BUT 2 days go I was drinking with this polish friend who rented the room to them in the first place, he had nothing good to say about them at all and I got wasted on vodka with the friend when I got home to my room apparently my partner told me they heard say polish kurwa or something when I was wrecked lol. Anyway I let out my frustrations when I was drunk, The fact that I never got a penny back from my £110 and supporting them 2 weeks free, and the fact they were allowing us to get a bigger place for them to stay then going to leave us I was pretty angry lol. And now I look like a dick to my girlfriends family, what should I do? its a big mess lol! I thought about finishing our relationship as my girlfriend is so immature and doing stupid decisions always but now I have a kid to think about how the hell can I escape this? of course I need to support my kid and I always want t see him everyday and raise him im totally in a mess. I don't give a crap what her sister of byfriend think about me as they shouldn't have even asked to stay here, they saved no money when renting £90 a week so why should I support them? he wasted his money on a tablet bitcoins and I know he sels lsd blotters in Poland! what should I do?