My dislike and suspicion of HRT is well known so I won't go into it here.   While my objections are serious and long-term, I do have a more down-to-earth reason for not being as pro-hrt as some people might think that I ought to be.     
   I have had two trial periods on oestrogen and on both occasions I have gained very significant amounts of weight in a disturbingly short space of time.    So what you might be thinking.   "All you need to do is cut down on your calories and/or increase your amount of exercise and bingo there is your problem sorted."    Well, I can give an excellent reply to this.   I am not, nor have I ever been a big eater.   My mother tried to fatten me up when I was a boy, and it did no good.    I can only eat a certain amount and no amount of coaxing or parental disapproval could change that.   I don't want to give the impression that I am some sort of modern day Luigi Coranado(sp?) but excess calories is not my problem, and neither is too little exercise the problem.  I am up and down stairs all day, lifting and laying, bending, twisting and stretching so under-exercising is not my problem.   I suppose you may be tempted to say,  "okay, so hrt makes you fat what of it?"    Well, being fat would present me with a wardrobe problem or at least greatly exaggerate my existing one.   At the moment I can't really wear dresses or long-sleeved tops, blouses, cardigans, and other knitwear.   A dress that fits me perfectly on the shoulders and bust is very often loose at the waist and hips.   From below the chest it looks as if I am wearing a dress two sizes too big.   Skirts thankfully aren't a problem as I can wear short skirts just above my hips and longer skirts sit on my waist.    I have one dress that I can get away with wearing and that is because it is close fitting and I wear a thin belt to prevent the lower half from flapping in the breeze.   As for long-sleeved blouses etc.  I have because I have long arms to wear a size of two larger than my chest size to get the correct sleeve length.    As a consequence of this some of my clothes don't fit properly which makes me feel self-conscious.   Putting on hrt weight would exacerbate this problem and also drive me into the unflattering cuts, styles and colours of what manufacturers are pleased to call 'plus-sizes'.   Also when I was on hrt unbeknown to my mother.  Clothes that did fit fine started to look too short and too tight.   I started to display a Winnie the Pooh look.  That is a noticeable muffin-topped gap between my trousers/skirts and my tops.   
   Sans HRT I can at least wear fashionable clothes.  On hrt and I would end up looking like Homer Simpson in a dress.  I don't want to be on hrt and be fat, frumpy, sexless and unhealthy.   So unless something can be done about my epic weight gain then hrt will cease to be an option for me.
I hope that this more down-to-earth example has helped explain to you why I am not singing the praises of hrt to anyone who will listen.    If hrt works for you and you don't start to look like a trainee Sumo wrestler then go for it with my blessing.  But please do remember that some people in our community get adverse effects on hrt and have to drop hormones for either the short-term or the long term.

Was your HRT trial under medical supervision? 

Understood. Did you mention the length of your trial periods? I have heard of some people responding to hormones in such a way, but I wonder if the change is temporary... Have you tried Estrace or it's generics? It's pretty polished up... Serious rapid weight gain is probably not a thing you just "try to wait through," though, huh?

Well, there are people who have transitioned without HRT. You just live as a woman for the required length of time and then do surgery if it won't produce complications somehow. Try pilates an / or yoga, because they can slenderize your body, creating a slightly more feminine physique. There are lots of clothes out there that are made to compensate for unusual builds.

I was rather naughty I bought hrt online.   My first 'trial' lasted 6 weeks, and the second trial a few months later last just over 4 weeks.   I gained around 30lbs in weight in the first trial and 21lbs on the second.   I started taking spiro the first 10 days of the first trial but as I didn't like the taste or the idea of watching my potassium levels I stopped taking it.   My mother and sister didn't know about my self-medicating and I think my mother was a little suspicious when I kept asking 'does this have potassium in it?'
    I know that self-medicating is frowned upon here at Susan's, but please be assured that dosage wise I was always ultra careful.    I took the smallest dose possible and often I took one pill and then waited 48 hours before taking another.   I have never been one of those people who believe 'if one is good, two is better, and three are great.'     I saw on I think Dr Lawrence's website her dosage recommendations for hrt beginners and I was taking only about 15-20% of the dosage she suggested.

I liked the calm, mellow, sense of rightness that I got with oestrogen, but you can get those feeling with slow deep breathing and/or meditation.