I am so sorry for the loss of your partner. It sounds, however, like he left you with an amazing legacy. As all true soulmates do, he triggered your tremendous appreciation of life, including making you feel like a million bucks. Yes, yes, YES!
With regard to your fear of being judged, I think we all share that feeling from time to time, depending on the situation and how emotionally invested we are with the people involved. Normally, one would like their family and friends to be proud of them and approve of their choices.
It appears that you really love your in-laws and that their opinion strongly matters to you. Chances are that you were fully accepted into your extended family, they fell in love with you, and they were so joyous that you made their brother/son/father so happy. They shared your sorrow over his loss, and you all banded together to weather the emotional storm ahead.
What usually happens next is that you want to keep this extended family close in your life, but you are afraid to tell them that you wish to date again. Do they never want you to date again? Or do they want you to wait longer before you do?
You don't have to tell them that you've just signed up for an online dating service or that you went for drinks with the cute guy in the next cubicle after work (much TOO much information). But if you are really interested in someone, you can start to slowly drop hints that you are resuming your social life by mentioning certain events or circumstances, like, "OMG, I can't believe how bad the traffic was on the way to the concert. Luckily, my friend, Luke, was there to navigate and find the best parking spot." Or you can interject into conversations something like, "Oh, yes, Kevin and I visited those campgrounds too! Weren't they gorgeous?"
Introducing this new man in your life to your existing extended family may seem like a daunting task, but it can be so easy if you do it slowly on your own terms. Ease them into the idea that you have a separate life beyond their jurisdiction ... and that your privacy is paramount!
I am sure that your in-laws don't want to keep you in a bubble for all of eternity. Yet, they still want to protect you going forward. They can't help themselves. It's up to you now to make sure they feel your love, while at the same time, respecting your privacy.