trying to end it again and again

Had an appointment with a clinician Friday. Setting me up with a psychiatrist supposedly in the next week or so to talk about meds for the first time. Issues that can't wait till then:
I keep trying to break up with my first boyfriend of over a year. He is able to calm me down most every time it happens, and make me see why I'm doing it is not for the right reason, why we should still be together, etc. If he is not able to, I come around pretty soon after and beg for him to take me back. I can't tell if I am doing this because I know deep down we aren't right for each other, and that the best thing I can do for him is to set him free, or if it's just my crazy mood swings- pushing him away because I am not happy myself, and I am thinking the unhappiness has something to do with our relationship too, as opposed to just my mental issues, that the "fog" of whatever I have that I feel like clouds my thinking half the time is making me do this.
Psychologist is leaning towards depression or bipolar. I'm not ruling out something else just because I feel like I create a lot of my problems for myself... I feel like I am more comfortable being sad than I am happy, that I like my emotional roller coaster in to depression, and that I think and do things just to get back to that emotional place.
I do not trust my thoughts anymore. I question everything I think and say and do.
My question is: how do you all separate your emotions, mood swings, and/or doubts from what is real in your relationships? Have any of you found a particular therapy technique (or anything really) to be helpful in learning to trust your feelings and learning how to separate yourself from temporary emotions? Learning how to protect your loved ones from the decisions you make while not thinking clearly?
He is not answering his texts and I fear I've done it for good this time :'(

I know it's hard, I've gone up and down and been conflicted in my marriage for a long time.... I sometimes think I may be co-dependent....

In the end, I really know she's right for me... but my mood swings come from the fact that I worry that I may not be right for her.... it's like she has all the power in the relationship because I feel like I need her more than she needs me. Does that even make sense? Intimacy has been an issue because I am more needy in that way than she is, so that's where my conflicts come from. We met very young and have been together for more than half our lives together now... so I can't imaging being with anyone else... but since I feel like I am chasing all of the time, I wonder if someday she'll bail... even though logically I know it's unlikely, it's a crazy feeling.

So to deal with it, I work out... that helps me a lot! I get perspective and it gets all of the endorphins going... stay away from alcohol and recreational drugs, there is no help there ever..

If you are young, I think that you should try to date other guys.... there are plenty of men out there.... maybe someone else is a better fit... if not, you can always get back together with your first BF. My next door neighbors dated in college, broke up, then got together at 35, and have been married for 12 years now happily, so it does happen!

i feel like i'm co-dependent, too. at least, every time i make him really happy i get happy. when i disappoint him or make him angry, i get so sad he ends up having to comfort me, even though he's the one who should be upset. i understand what you're saying about your wife, it feels the opposite here. he's so sure i'm the girl of his dreams; he's dated like 10 or something girls before me, whereas i have no dating experience. i had been using alcohol or weed occasionally when i felt all depressed, so i guess i need to hop on the exercise train and try that. that's good advice, so thank you. i am young, but i do not want to date other guys, and my boyfriend has stated that once we break up, we are done for good. he does not want to be just friends with me, and will not want any contact, and has said that he does not date someone after breaking up with them. so i am aware that it happens, but it won't in this case :\

Alcohol and weed can affect moods. How are you going to manage to get a proper treatment regiment from a psychiatrist, while still participating in this recreational use?

Have you considered making a list of what it is about this relationship that feels right, and what about it feels wrong for you, as a person? You are scared to break up, with him, because he's already professed, when it's done, you will no longer be in contact. You mention, he has a way to calm you down, and see that he's right about staying together and your 'wrong' for wanting to break up?

I'm more interested to hear more, about what brings you to the point of wanting to end things with him. Not convinced it's due to your moods? What brings on these depression 'moods' that leave you feeling you want to break up with him?

Have you told your therapist that you feel like you are doing it to yourself? Have they suggested dbt or cbt?