DP's son making me feel like I'm in a relationship with both of them

I think your DPs son has been used to having an adult relationship with his dad and being spoken to as an equal. You probably need to speak to his dad about how he would like it handled. When I was teaching I worked with a lad like that and it was incredibly irritating as I had to point out that he wasn't an adult. He had an opinion on everything. That said, he was a nice lad with a good heart. He had just been given too much leeway by his mum and dad.

My sympathies are with DP's son. You move into his home and try to exclude or ignore him. It is HIS home.

Did you not read? She said....I made a tea and biscuits. The son was elsewhere in the house. He wasn't a visiting guest that you would seek out as is polite. He lives in the house. If I were to make a cup of tea and have a biscuit I would make my partner one too. If for some reason I had a child who was cloistered in their bedroom doing their own thing. I wouldn't necessarily knock on the door and ask them if they wanted to interrupt their free time to come sit in my home office and partake in hi tea.

The adults were working from home in the same room. It was a work day. Not a family event or guests visiting.
I'm sure the son when popping down to make himself a cold beverage didn't think to knock on the office door and say dad, lady living with us. Do you want a glass of squash. Of course not.

What is wrong with people on here.

To open I will admit that I have skim read this thread. But I do not see much empathy for the OP. As I see it this is new family trying to establish some boundaries even after a year. I do read the biscuit and breakfast thing as a mistake that I would not share in public. Somehow the three of you need to find a way to make this work. From my point of view it is not easy doing this as your family matures without the added issues around being parachuted into an established father son bond.

How would you feel if dp made himself and dc a drink and biscuit or breakfast and said to you that you are capable of making your own. You chose to become a family of three.

I don’t think you’re ready to be in a relationship where children are involved.

You want them to be seen and not heard.

He wasn't in the room when he didn't get offered the biscuit

He sounds like a typical kid. You sound like you are excluding him.

Alright, listen up. You’ve got a tricky one here, but it’s not unsolvable. First off, yeah, this is normal to an extent. The lad’s adjusting to a big change – you’ve moved in and his world’s shifted. He’s not just sharing his dad anymore; he’s sharing his space, his routine, and probably a bit of his sense of security.

Now, it sounds like he’s struggling to figure out where he fits in this new setup. Kids, especially at that age, can act up or try to push boundaries when they feel unsure or left out. Doesn’t mean he’s out to make your life hard – he’s just finding his feet.

The key here? Boundaries and communication. Sit down with your DP first, get on the same page about how you’re approaching things. Then, together, have an honest chat with his son. Let him know you’re not trying to replace his dad or overstep, but you’re here as part of this family. Explain that some conversations and decisions are for adults, and that’s just how it is.

When it comes to those little moments – like the biscuit or breakfast – try involving him more casually. A simple “Fancy a brew too?” can go a long way. Small gestures, big impact. Give it time – this stuff doesn’t change overnight.

You are right. He's a kid

Everything about this post grates me 😅 Why when you got the biscuits out would you not just offer one? Or ask what he fancied for his breakfast? It sounds like to me personally that you don't like him that much. You've purposely left him out and he can feel it , not to mention after 5 years he's still partners child and definitely not your step son.

Sorry but ... the "12 year old doesn't understand the dynamic in the house". What dynamic the 12 year old child is expected to understand isn't clear but adults struggle with family dynamics at times and young children at 12 have enough to worry about in modern times (exams, social media, covid disrupting their education etc etc) without feeling disregarded in their home and having to learn the "dynamics". When you form a relationship with an adult who has a child, the child is part of the package. If you are having a cup of tea and biscuit and offering your partner one, I don't think it would take much effort to offer the child milk, orange juice, a biscuit, whatever they enjoy. If you are offering your partner the choice of a breakfast, ditto. This is his child and the child didn't choose the present situation.

OP you went into the relationship, eyes open, about DPs son living with him, why pretend now that it's only you and DP ?? Quite unreasonable as I see it

So three of you are in a room you feel the need to serve one but ignore the other....your unreasonable nobody would be so rude let alone to a kid.

I agree with this totally. Teenage years are hard, and he is trying to find his place as he grows into adolescence. Some of those interruptions about 'adult' things maybe his way of asking for explanations or clarifying understanding. He is also beginning to flex his muscles against his father. Firm rules and boundaries are the key. Bring him Into the conversation about making them. Be honest about your possible ND. Get everyone to talk about expectations and what can be done by the others to help manage them. Write these ideas/rules down; you lead by example and keep them. He does need to be treated more towards being a potential adult. This period is difficult for most families. They key is communication. Maybe schedule a family "revue" pizza night (or other treat) where you discuss in broad terms the past month and what the pinch points might be in the following month, or just call it a family scheduling get together where you discuss diaries and upcoming events and gently look back on the previous month. Whatever you call it, just make time for you to all talk together and all be heard.

His kid will always come b4 u, strange u rnt offering him a biscuit or food.

You are in a relationship with both of them. You moved into his home, not the other way around. It sounds more like you don’t understand the dynamic in the house and you are taking a very ‘children should be seen and not heard’ stance.

When he is an adult, if he still lives with you and makes 2 cuppas without asking you I’d imagine you feel the same.

It's hard enough parenting as a biological mother & negotiating parenting/house rules with a biological father ..kids push boundaries you don't t even know you've got & as for the difference in personal parenting values!! So I can only imagine the difficulty parenting someone else's teen without youth/child experience.

If you decide to stay in the house & give it another go, maybe think about doing a parenting programme with your local authority or watch some YouTube videos ..I'm found them very helpful .It's certainly not easy! Good luck 🥰

100% this. Also chipping in is how kids learn to & practice, how to discuss, negotiate, compromise and disagree.

As for the biscuit, personally it seems weird to only give one person a biscuit if there are other people present. Teens are especially sensitive (as well as hard work!!) & to actively exclude them seems unnecessary .. personally I'd be offering them first.

Why is everyone clinging onto this biscuit. 🤣.

Sorry I haven't read the whole thread apart from your OP, it sounds like you are excluding him. He will always remember this. You are the adult. He is the child. Make more of an effort with him. He is part of the family and was there before you were. Make more of an effort with him.

The DP needs to set some boundaries for his kid as things have changed. Doesn’t mean he loves his kid any less. Could the kid be ND?

my 15 yo DS is in bed by 10pm. I don’t care if he is awake and reading (no phone) but he needs to rest for school. I also need to have some time by myself and also with DH.

Wheres his mum?

I was an unwanted stepchild 10 months after my mum passed away.

I can imagine my stepmother saying the same kind of stuff, I was deeply insecure and just wanted my dad.

Offer the kid a drink and a biscuit, you need to make him feel included as its his home too.

He's been there for 11 years and you moved in a year ago. You are now a family of 3. As much as possible you need to operate as a family. He is trying to belong, and offering his opinions - kids do this - it's how they learn. How would you feel if he made drinks just for his dad and himself?