Best Of

First of all, no need to apologise. I also think it's really good that you have posted this as a way of documenting your struggles. Knowing that you have thread where you can write all your thoughts and feelings down relating to this issue can feel really helpful, I know!

It sounds like your last relationship really affected you given that your ex lied and cheated repeatedly. That's awful for anyone to go through, but perhaps more so when you struggle with emotional permanence.

It can be really easy to get caught up in a relationship and find that we have dedicated all of ourselves to someone and in doing so have 'lost' ourselves. I understand that you feel you try to spend as much time with your partner as you can because you overthink when you aren't together. It's also admirable that you realise that this can get unhealthy and that you don't want to get to the point of being upset when he wants to hang out with his friends. This wouldn't be fair on either of you.

Perhaps it might help a little to start regaining yourself? What things do you like to do or enjoy doing by yourself or with family or friends? When we have other things going on in our life, it can bring a bit of a balance in our relationship too, rather than just relying on our relationship for happiness.

It can be difficult to relax and enjoy things in the moment when we are worrying about what our partners are doing or feeling when we aren't there. Have you tried talking to your partner about how you have been feeling? Maybe you can come up with ways to cope, for example, he can give you something to hold on to when you aren't together to let you know that he cares for you, even if he isn't with you. It could be something like a little note or whatever that you can read when you start worrying. Something else that might help is to remember all the good moments you have had together and all the positive things you can still look forward to in the future as well.

I also understand why you might consider breaking things off with your partner. It must feel awful feeling this way and also not wanting your feelings to affect him. I'm also wondering how you would feel about talking to a counsellor about this? Counselling might be able to help you with emotional permanence issues. Relate https://www.relate.org.uk/ might be a good resource too.