Um, I think /r/relationships would be a better spot for your query than here... just my thoughts.
For your fitness stuff, dude, although you have made some great grounds, from your description and mindset, sounds like you still have some ways to go. Women come and go, but your health is just that, your health. If you want to maintain a healthy and active lifestyle, its a daily choice - period. It is something you do every day, week, month, year, etc. If you think you are unable to maintain focus on being active and losing the weight (and/or getting the physique you seek) while dating, then you need to make the choice of what is more important to you - women/relationships or fitness.
It is totally do-able to have both but to me, and this is a huge assumption, sounds like if you jump on the dating train b/c you think its the only one at the station (again, it's totally not...there will be another one in like 5min with even more women as you lose weight, gain strength and confidence again, and another after that, and another after that, etc etc) you are going to slip right back into you old habits and life style.
My opinion is just this, take the attention as just that - compliments regarding your hard work and determination. And use that attention/praise to keep pushing yourself, 70lbs in a year is a solid effort, but you can def keep going lower by taking better control of your diet and exercise regime. If you want to date, great, go ahead and do that. But you need to decide what your balance will be between the women in your life, your family, your exercise, and your diet. And if that seems too complicated, than you need to chose which things deserve the better focus.
But I'm telling you, straight up, women literally come and go. Just b/c you feel like you are missing out on opportunities does not mean there will not be others. Go on a few dates, reward yourself, have some fun, but don't think dating multiple women is the end-all-be-all of your fitness. But then again, maybe that's your intent of getting into shape in the first place, who can say? Again, totally up to you as to where you commitments and priorities lie for the duration of your life. Just bears repeating, fitness and a healthy life is a life-long choice - otherwise you're just doing a short term trend and will wind up right back where you were in the first place: out of shape, over weight, alone, and miserable.
Your life, your choice, dude.