Am I over reacting ?? UPDATE!!

So today my boyfriend of 3 years made plans to take my little sister swimming this morning around 9:30-10:30ish so we were both up and ready for when he would come.

He didn’t end up waking up till around 11:40-12ish but didn’t text me I only found out cause he posted something on his story on Snapchat, I messaged him asking if he was still coming and he ignored my text and left me on delivered( I’m still on delivered)

We have each other on life 360 together and it showed he left his house so I thought okay cool he’s coming over no big deal but he was going towards our old school. He has younger siblings who go there so I thought nothing of it, but then he kept going to and girls house who I do not like because they had a almost drunken hook up 2 summers ago when we were in a really bad fight and we’re temporarily broken up. Nothing based him fingering her. To this day I tell him how that still hurts me and I don’t want him around her, she does have a boyfriend now and he goes over there with both them there to smoke weed.

I don’t like to smoke or people who smoke in my opinion, so I got mad at that as well he still hasn’t texted me all day long , and I’ve texted him saying how my little sister is very hurt and upset that he flaked on her this morning cause she was very excited to go swimming with him.( I took her my self a hour later after he was late for a few hours and we had a blast!) I called him multiple times to see if we could talk about it or he could at least explain to her, and he ignored all the calls until a hour again he declined the call and said “ hold on.” I looked on Life360 and he’s back at that’s girls house.

I do not know what to now because I have voiced my opinion to him and how he’s hurt my little sisters feelings ( she’s 9 ). But I also keep apologizing to my sister about this too.

UPDATE:

Firstly I wanna thank everyone for being so supportive and all the advice this has received!!!

This morning me and him met up at the local park cause I figured it’s a nice neutral ground for us to talk out before the kids came to play on it. And I brought up all my concerns and anger from yesterday and with my little sister being involved and he deeply apologized and told me what he was doing and why he wasn’t answering his phone, I started telling him he needs to work on communication more or this relationship won’t last much longer because me and my little sister don’t deserve to be treated like that especially how young she is I don’t want her around that anymore.

He addressed that he was in the wrong, and I found out he was with another group of friends but he wouldn’t tell me their names cause he thought I’d over react , but I told him to tell me cause my trust for him was slowly disappearing and he told me a couple guy names but there were a couple of girl names, in the mix. And part of me is still very concerned, because he brought up the girl ( with the drunken fling ) and her boyfriend were his friends and he was gonna hang out with him... and that sat very uneasy with me, but I don’t wanna be the type of girlfriend to tell him to block people.. but I also don’t trust girls because I know almost all of us has ultimatums when it comes to a guy they have a crush on...

We are gonna have more conversations to slowly build back up the trust and have better communications but I still feel like I’m in the wrong...