Im not sure I want to go through with my wedding

Im (30f) an overthinker and I don't know if I'm just making myself spiral or if this is how I feel.

My partner (30m) and I are high-school sweethearts, so we've been together a long time. As you can imagine, our relationship wasn't smooth in the beginning as we went through our teenage phase and was actually quite unhealthy. Once we matured, we cut the shit and learned to communicate better and live together. I never quite had the desire to get married.

Last year we went through a rough period where a lot of unresolved issues came up and I think we were both in a place of thinking to break up. I went away for 2 weeks and during that time of vulnerability on both ends we did things. He emotionally and almost physically cheated on me with a coworker and I downloaded Tinder on my vacation and flirted with guys.

We took a serious look at our relationship and had great and real discussions on where we wanted to take things. Ultimately we decided to stay together. He proposed a few weeks later and I was very surprised but said yes.

We are now planning our wedding and I am getting so overwhelmed. As much as I get excited for things I also feel scared, nervous and just want to check out.

My partner and I have been through so much but I just don't know. I don't always feel love from him. I feel like he makes shitty comments towards me.

I don't want the obvious answer to just be 'break up with him' because that's easier said then done after 14 years with a home and pets together. I love his family and my nieces.

I just wanted to put this out into the world. And yes, I'm seeing a therapist. Aren't we all nowadays?