I find it useful to remind myself sometimes (frequently) of what Buddhism calls 'skillful means', here applied to our intimate relationships.
eleven things to give up in relationships
The idea that your partner or anyone else is here to make you happy and to meet your needs. Your partner is here for his or her own journey on this earth; if you can support each other in your journeys and adventures then you have a chance of real happiness.
The view that you and your partner sail in the same boat. You are, always have been and always will be in two boats*; the choice is whether you steer side-by-side for the same open sea, or shore, or not. What you have in common is the ocean.
The need to merge or fuse with your partner. True union isn’t possible except when two individuals are clearly differentiated, knowing themselves and their partner as distinct entities. Work instead on knowing who you are, and seeing clearly who your partner is. That way, there’s a chance of real love and interdependency rather than co-dependency.
The need for that Other to be like you and to agree with you. Showing another who you really are and engaging with who the other is is an act of love; needing their agreement and approval before you can be who you are can be narcissistic, egotistical and insecure.
Controlling, whether by fault-finding, withholding, blame and coercion – or by praise. All are manipulations, and driven by fear. That doesn’t mean to say you can’t appreciate, out loud, who your partner is, nor ever express something that's pissing you off – it's more whether you are co-opting this to serve your fears. (There's an associated issue here: that of self-disclosure. This is a prerequisite for intimacy, but it's important to be aware of whether we use this as a manipulation to have the other reveal him- or herself to us, or as a genuine desire to share who we are with that Other without necessarily expecting reciprocity.)
The association of love with mind-reading: ‘If you really loved me you’d know without my telling you what I need.’ Instead, commit to knowing for yourself what you really need, and be willing to show that to your partner. Equally, learn from him or her what s/he needs.
Expecting the other to always ‘be there’ for you. It’s simply not possible when the other has his or her own life and journey, and s/he is not your mother/father.
Taking everything another says or does personally. While you may be offering him or her a 'hook' to hang their stuff on, another person's 'stuff' remains their stuff, and probably says more about them than about you.
Reacting. Instead, learn to respond. What this means is denying yourself the momentary satisfaction of blowing the other out of the water with emotional heat (you might feel it, but that doesn’t inevitably have to lead to exhibiting it), instead seeing clearly what the situation needs from you. You may still find you need to raise it with your partner anyway; if so, it helps if you can give yourself time to calm down so it isn't merely an attack. If you take time out, you may find you don't need to launch anything at him/her, but adjust an expectation of your own, or at least trace the roots of your reaction and its previous baggage (because there usually is some).
The need to blame – self or other. Instead, take responsibility and change a pattern for the better. We’re all human and we all get it wrong sometimes as we learn, and that is simply how it is. Learn to love yourself; then you can love another.
Struggling – with yourself or another – to be anything other than who you are/the Other really is.
But you don't have to believe me; just try it for yourself... And no, of course I don't manage it myself all, or even much, of the time! And this list clearly could go on and on, and no doubt at some stage it will.
* The boat image is from David Schnarch's book Passionate Marriage.