I broke up with my boyfriend during summer, but before I went back to uni I started seeing him again.

Now we see each other quite a lot (although we're not together).

Sometimes, everything feels perfect and I want to get back with him. I sometimes feel like I want to spend the rest of my life with him, and it hurts to think about him with anyone else. I really do think I love him, I can barely deal with being away from him. He really seems like the perfect guy; he's honest, kind, is just the most caring guy I met. He really has a massive heart. I don't want to throw that away. He has told me he can see a future with me.

However, I also frequently go through periods where I get irrationally annoyed with him. I think about ending everything for good a fair amount. Sometimes I just want to tell him it's over and never see him again.
I also find he doesn't really turn me on before sex anymore. I'm definitely attracted to him, but whenever we have sex I never really get turned on during foreplay so we just skip into it sometimes, and the actual sex is good.

I'm really at a loss. Sometimes I sit and think about how much I want to live my life with him, but other times I sit and think about I need to end everything asap and not see him again.

Why am I feeling such contrasting emotions? I really don't know what to do. I know I'd regret ending things for good, but I also can't deal with the negative points I've said about, and I feel like I'm closing myself off to other people who could make me happier by seeing him so much.

I'd really love some advice on this 

I believe you need to seriously sit down and think about what you want and what you need. This doesn't sound healthy, you're being unfair towards your boyfriend all because it hurts to be by yourself and you can't imagine him with anyone else. This doesn't even sound like love to me, it sounds like you've just gotten comfortable having him there but you don't really want him there. This isn't just about you it's about another human being as well with thoughts and emotions.

There’s lots of things that can come to mind when you feel these sort of emotions that turn you down, against him and the way you feel...

Most of it all could be in the way that you both really are comfortable with each other, it seems like you guys are bonding more than the average which makes these feelings go everywhere especially when he makes you feel down at situations..

It’s to me all because you are very comfortable with him but something out there is giving you need for a more spaz that you are looking for...

I would say calm down the relationship with him, and potentially go out and keep the look out for friends,
As soon to see if you can really find what’s out there for yourself (more positive feelings)

Definitely do not use or abuse the comfortability that you have created with your boyfriend, keep him around cause after all you said he makes you happy most of the time