I'd back off from the man and see if he misses you. This is the time to see if he's a keeper and right now he is finding it impossible to make room for you  and his son in his life. This sounds like a new normal for them both, has he been divorced long?  Don't get anymore attached right now and watch this unfold. Don't hesitate to end it if it's not for you. Plenty of fish in the sea.  

I can understand his son's position.  He only sees his father every other weekend, so he wants to spend time with his father.  And if his father is in a casual relationship, it's fine and appropriate for him to send you home in order to spend time with the kid.  I think the problem is that you don't view this as a casual relationship, and it's not casual the other 26 days of the month.  YOUR needs aren't being met when you're excluded every other weekend, and from a significant part of his life.  

I'd pull back on the relationship.  Your boyfriend doesn't seem prepared to take the next step, but he wants all the benefits.  It doesn't sound like he's ready for a real relationship where you're an important part of his WHOLE life.  There's no indication of when or if he might be.  If you're ready for more, and want to marry or live together or have children, your timeframe and his might not mesh.  And don't blame the kid - the 7 year old is telling your boyfriend what he wants, but your boyfriend is making the decisions.   

BF is placing DS over you .  This type of relationship will never work.  Where kid runs the house. 

Don't go back.  Leave that failed family shallow gene pool to their mutual admiration society and get on with your life.  Keep in mind... if you pollute your own gene pool with this guy, you know what to expect from both the father and your child.

Save yourself and find an actual man of quality to be your mate.

Besides, what woman of substance would want a ball-less man who allows a 7yo to dictate his life?

Good luck.

You're a side chick

I would know..I was one too until I came to my senses and realized I was settling for breadcrumbs...then I ended it

Kids are manipulative. My exSS5 was. And I ended up hating him for it. These kids know exactly what they're doing and the sad thing is...they will always win. You will always play second fiddle to his son and possibly the ex. 

It's a miserable life and it doesn't get better. It gets worse. By the end of my relationship I felt like I was going to end up in jail because of how much I hated exSS. I thought one day, I was just going to lose it. 

You're getting a little taste of what life will be like if you move in. Can you imagine this becoming a regular thing for you? Because that's what it will be. Might be cute to play house now but wait until you get put on the back burner every other weekend in your own home...wait until you're nothing but a roommate with no spot on the couch and no rights to anything in the house. The dad making little effort to keep you, but still expecting you to stay so you can be a convienant little addition to his life when he wants you in it. 

End it and find a child free guy who will put you first

This is not acceptable AT ALL. A young child his age cannot dictate nor decide when you get to stay at his father's house. Your man going along with it shows that he barely respect you and your feelings. It's understandable that the child might want to spend time alone with his dad or May be afraid of your presence as "stealing his dad" but not on this terms. This is just disrespectful and I can't believe your boyfriend is accepting any of it. It's probably easier said than done but you should move on. 

If your BF cannot balance fatherhood and a relationship, he should remain single. He is getting his needs met, you are being cheated, having a child dictate the terms of your relationship.

all of the above !  this happened to me in the beginning also ,, never gets better only worse and your BF has no intenetion of standing ground with his kid.  Only you can stand your ground.   Lay all your cards on the table before this continues and if you are met with hostility or your feelings are rejected ,, thats where you will always stand .  Find a guy without kids 

Time to treat him like a casual boyfriend. 
1. no expecting that you're just going to drop  everything to spend time with them 

2. See his kid on YOUR terms not theirs. This means outings with kid need to last less than 90 minutes because you have other things to do and you can't tolerate it for longer than that 

3. don't keep your schedule wide open on his kid free weekends 

4. if he invites you to hang out with his kid give them a time frame that will work for you and make them come to you so that they have to leave when the kid gets tired. Drive separately. Don't let that kid in your car or your house. 
5. don't buy gifts for the kid. You're a casual girlfriend. 

What do you want out of this relationship?

Whether you want serious or casual the lil dictator SS will call the shots. I wouldnt put up with this even in a friends with benefits situation TBH.  

Friendship/relationships should have equality. Yours doesnt.

Save yourself the headache and move on. So early in this relationship and already you feel tossed aside. Not a good predictor to your future.

Do not let this guy think you are so agreeable, or easily thrown aside. We only let others treat us poorly if we let them. I made that dang mistake for many years. As a result I threw away the opportunity to be a bio mom. Now that ship has sailed. To make it worse I played SM to an ungrateful lil byatch. Trust me you dont want this.  We cant go back BUT we can always move forward.

Learn from this site.

You and this man have been seeing each other long enough for you to know where you stand.  If you don't then he will never be ready to include you into their nucleus. The child seems to be an excuse to keep you at arms distance, not to mention he may always put his child ahead of you.  As a single mother I had to keep my daughter's health and safety first, but I did make equal room for my ex-husband.