Well, Hi Lorna!!!

Guess I'll give you my .02 worth, since I have some personal experience with this stuff.
Based on the experiences of the 35 people in my support group and myself, your reasoning behind transitioning may be flawed. As Anita and Jan W. suggested, you sound almost like transitioning would be 2nd best in the hope it would change the balance somehow.
Most people with GID transition because there is just no other choice. It is a decision about whether they will continue to live, or not, and they generally are pleased with their choice since it removes a very big conflict that invades every part of their lives. I can't really describe that conflict, even though I have lived with it for so long. The best I can do is that you just don't feel complete, don't feel whole!!! And it always sits there in the back of your mind even when you are doing something enjoyable, like a monkey, a burden on your back. And then you find you have spent the entire day doing nothing but trying to divert yourself from thinking, and realize that you have been doing the same thing for WEEKS!
And sooner or later, you come up against THE WALL, and you know you don't care if you live or die, and then you think maybe death is preferable, as it is an end. If you survive the wall, either through intervention following an attempted suicide, or your own bedrock level of basic optimism or hope, you get a therapist, get on hormones and feel some balance in your life for the first time. Even then sometimes it can seem it varies between being stuck in snail snot without any progress, to riding a whirlpool, going faster and faster as you approach the center, your goal.
It seems that everyone has their own wall; for some it comes early, for some later. If you
are GID, you may be a ways from hitting your wall if you think you can put it all on hold and wait for a relationship. On the other hand, if you can start talking with a therapist, you may be able to avoid the WALL altogether and ease into transition. If you have been butting heads with the wall already, find a therapist and let any interpersonal relationship that may come happen or not. Your going to be busy anyway.
Most transitioners who regret the transition (about 3% to the best of my therapist's understanding- She has had one out of 60) are often people who can't let go of the male privilege they lost, even though they are gender dysphoric; find themselves tied to the family they have had and still feeling guilty for transitioning and upsetting their lives; are mis-diagnosed with or without their own unconscious duplicity; or deliberately deceive a therapist becasue they think transition will "cure" all their problems. This, of course doesn't happen, as instead they find they have another entire suite of problems related to being a woman (employability, social standing, being taken seriously in a work environment, the glass ceiling, prejudice) in addition to being suddenly again the wrong gender and regretting transition. Regardless, they always blame the therapist!
The support group I mentioned above is about evenly mixed between M2F and F2M. One married her current SO just before transitioning, but after her divorce from hir first wife. They have been able to stay together, but acknowledge that at times there is tension. Several others have found SOs since they began transition. One M2F and her SO are bi, and in the other case of M2F, the SO is male and loved the person before finding out they were transitioning, but while they were living in their new role. In other words, they never knew the person as a male, only as a female with a bit of a birth defect. Two of the F2Ms have SOs, and one of them has been with his SO since before even hormones, and the other has met the F2M in the last 6 months during transition. One of the other F2Ms has lived in a, well technically, lesbian realtionship for 13 years, and has a kid from a previous marriage that will have nothing to do with them. Most (there are four including your humble servant who are exceptions) married have had children in the natural course of events, thinking that would "cure" them, or at least give them motivation to be part of a "normal" life. Lorna, based on their experiences, marriage and/or kids just doesn't eliminate the need to transition, and
may only slightly delay it. But like CDing, it just won't go away.
And it seems that most people with GID do find it hard to maintain a realationship with the opposite apparent gender, especially M2Fs. It is like the ggs unconsciously realize after so long a time that there is something going on, and unless it is to their liking or they are set in the traditions of marriage, they will find a way out. It can also be the behavior of the unhappy sufferer that will bring it to a head. The GID, especially near the wall, can make one grouchy and hard to live with, contrary, and generally a SOB, though not often violent within the family.
If you
need to transition, you will not put others or a possible nebulous future relationship before satisfying that need. It is an incredible investment of time, money, emotion and loss, and you must be certain that is what you have to do, because if you find out it was a mistake after the final surgery, that's just too bad. On the other hand if, as you age, the dysphoria becomes primary and you find your wall without the help of a therapist (as it has with most of the people in the support group) because you do
need to transition, then it will happen no matter the status of your personal relationships with others.
If you truly believe this will likely be your future, the time to start is now in your thirties, not in 7 years when the hormones will be less effective. So if you really think this is you, chunk whatever money you can in a therapist's pocket now, and talk your head off and tell him or her just how you FEEL, including any ambivalence you may have. There has been a lot of stuff written by people that don't like therapists, but the best will help you really come to an understanding of your true needs.
Well, OK, so I rambled. Just be sure, Lorna, about what you want vs. what you need.
Love, Carolynn